Note: this is not a re-ranking of current prospects. A new top-50 prospects list will be released this off-season.
10. Max Stassi
The A's dealt several top prospects just before the start of the season, and Stassi was one of those players. The Yuba City native was part of a three-player package sent by the A's to the Houston Astros for shortstop Jed Lowrie. Stassi got off to a slow start with his new organization when he was diagnosed with a sports hernia during spring training. After having surgery to correct the issue, Stassi rehabbed for the first six weeks of the season before joining Double-A Corpus Christi. He has spent the entire year at the Double-A level.
It has been solid, if unspectacular, year at the plate for Stassi. Overall, Stassi has a .248/.324/.424 line in 165 at-bats through Sunday. He has five homers and a 44:14 K:BB ratio. Stassi had a strong first two weeks in the Texas League, but he slumped in June, reaching base only 26% of the time. In July, he has a .381 OBP in nine games.
Stassi's best asset as a player has always been his defense. Recovery from shoulder surgery curtailed his throwing some last season, but he has thrown out 35% of would-be base-stealers this year. He handles pitchers well and has excellent mechanics behind the plate after struggling to block balls early in his career. If Stassi can become even an average hitter, he should be an asset in the major leagues thanks to his defensive abilities. At 22 years old, Stassi is on the right path towards a long big league career, provided he can stay healthy, something he has struggled to do as a pro.
Status: Learning the Texas League
Robertson's season also got off to a slow start. The A's second overall pick in 2012 injured his knee during the A's fall Instructional League. His rehab from that injury took Robertson through the first few weeks of the season. Robertson joined the Low-A Beloit Snappers just before the end of April, and he has been the Snappers' regular shortstop ever since.
Robertson has had an up-and-down season at the plate in the pitcher-friendly Midwest League. Through Sunday, he was sporting a .259/.344/.380 line in 234 at-bats. League average for the MWL is .254/.330/.375, so the 19-year-old has certainly held his own. Robertson struggled early in the season controlling the strike-zone, but he has improved his K:BB as the season has progressed. He hasn't hit for a lot of power yet, but he has shown power in batting practice and the A's believe that will develop in-game for Robertson over time.
Defensively, Robertson has opened a lot of eyes. When Robertson made his pro debut last season, he was often slotted at third base so that 2012 top pick Addison Russell could play short. However, with Russell not on the same team as Robertson this year, Robertson has returned to his natural position and he has shown above-average range and arm strength at short. Eventually the A's might have to make a decision about how to play Russell and Robertson together, but for now, the A's will continue to develop both as shortstops and let the position battle work itself out in future years.
Robertson receives high marks from coaches for his work ethic and determination, although at times he may try too hard. If Robertson can manage his effort level effectively, he has a chance to be a solid number two hitter with a plus glove in the big leagues.
Status: Settling in at short
8. Miles Head
It has been essentially a lost season for Head up to this point. The corner infielder had a big first year in the A's organization last season, but he has struggled with injury and ineffectiveness this year. The former Boston Red Sox prospect hit .333 with a 968 OPS across the High-A and Double-A levels last season. He was sent to the Arizona Fall League but he injured his shoulder during the first game of that season and missed the rest of the AFL schedule.
The A's had hoped that Head's shoulder would be healed by the start of spring training. He was invited to big league camp but came into camp out-of-shape, a side-effect of trying to rehab the injury. Head was sent back to Midland to start the 2013 season, but he struggled badly out of the gate and had a .196/.264/.264 line through 40 games before he was shut-down with shoulder soreness. He has been rehabbing the injury since mid-June.
It isn't clear whether Head will return to Midland this season or if he will need the rest of the year to correct the shoulder problem. There is no doubt that this has been a disappointing season for the Georgia native, who showed impressive bat speed and plate coverage last season. However, Head is still only 22-years-old, so while a lost season is never a good thing for a prospect, it is something he has time to recover from.
Status: Trying to get healthy
7. Brad Peacock
Peacock was another part of the package the A's sent to Houston for Jed Lowrie. The right-hander spent just one season in the A's organization. Acquired in the Gio Gonzalez trade with Washington before the 2012 season, Peacock was expected to be a part of the A's rotation during the 2012 campaign. Instead he struggled for most of the year with Triple-A Sacramento, posting a 6.01 ERA and a 139:66 K:BB in 134.2 innings.
During his time with the A's, Peacock struggled to maintain consistent mechanics and that impacted his command. Command issues plagued him again early this season, especially when he was in the major leagues. In nine major league outings (five starts), Peacock walked 17 and allowed eight homers in 29 innings. His MLB ERA for this year is 8.07.
He has been better in Triple-A Oklahoma City and he may be nearing another big league opportunity. In 11 outings for the RedHawks (10 starts), Peacock has a 2.73 ERA. He has struck-out nearly a batter an inning (57 Ks) and he has walked a more reasonable 3.03 per nine innings (as opposed to 4.41 with Sacramento last year). His HR/9 rate is also below 1 after sitting at 1.07 last season. The Astros are playing for nothing but their future the rest of the year, so it is likely that they will give Peacock another extended look before the season is done.
Status: Improving in Triple-A
6. Grant Green
Green's first week in the big leagues hasn't gone as well as he would have hoped, but that shouldn't take away from the strong season the A's top pick from 2009 is having. After putting up a .296/.338/.458 line for Triple-A Sacramento last season, Green returned to the River Cats in 2013. In 81 games with the River Cats, Green has improved his production in every offensive category compared to last year, posting a .318/.374/.500 line with 11 homers and 25 doubles in 352 at-bats.
Green has put up those numbers as a second baseman after spending most of last year in the outfield. Originally a shortstop, Green has endured several position switches since being moved off of shortstop midway through the 2011 season. While still learning the second base position, Green has looked better there than at the other positions he has been asked to play over the past two years.
Since his big league call-up, Green has had three starts, all against left-handed pitchers. He hit well against lefties with Sacramento this season (986 OPS) but only had 71 at-bats against them. Green has been an everyday player his entire career, so he is adjusting to life as a platoon player while also learning the big leagues. Green isn't a finished product defensively, but the A's have seen enough from him to believe that he can be an adequate defensive second baseman with the ability to be an asset at the plate eventually. With the A's in a pennant race, Green won't get too much leeway to produce at the big league level. That said, it will take more than three starts for the A's to decide that Green isn't ready for the big leagues.
Status: Getting his feet wet as a big leaguer
5. Sonny Gray
The A's had two former first-round picks make their major league debuts in Pittsburgh last week: Green and 2011 first-rounder Gray. Like Green, Gray debuted in a new role. Exclusively a starter during his professional career, Gray made his first big league appearance out of the bullpen. His two-inning performance versus the Pirates was impressive; Gray struck-out three and walked none in two scoreless innings.
Gray's major league debut was very much indicative of his performance with Sacramento this season. The Vanderbilt alum has dominated the Pacific Coast League and would have been the PCL's starting pitcher in this week's All-Star game if he hadn't been promoted to the big leagues. In 16 starts, Gray has a 2.81 ERA and a 107:34 K:BB ratio. He has allowed just four homeruns in 102.1 innings in a league known more for its offense than its pitching.
Last season, Gray struggled at times with his command. He worked on a mechanical adjustment with the finish on his delivery and he started to see better results by the end of the year. Gray also improved his change-up, an important third pitch to pair with his hard sinking fastball and plus breaking ball. Whether Gray remains in the A's bullpen for the rest of the season or eventually slots into their rotation remains to be seen. Either way, he could be a big asset to the team as the A's push for a second straight playoff appearance.
Status: Beginning his big league career
4. A.J. Cole
Cole has a lot in common with Gio Gonzalez, the least of which being that the two were traded for each other before the 2012 season. Both Florida natives and high-round high school picks, Gonzalez and Cole have the rare distinction of being traded for and by their original organizations. In Gonzalez's case, he was dealt from the White Sox to the Phillies and back again before eventually being traded by the Sox to the A's in the Nick Swisher deal. Cole was traded by Washington to Oakland before the 2012 season and was then traded back to Washington by the A's before this season in the John Jaso deal.
Cole's one season in the A's organization was somewhat disappointing. He began the year in High-A, but he struggled badly with the Ports and was sent back to Low-A after posting a 7.82 ERA in eight starts. Cole rebounded well in Low-A, dominating for the Burlington Bees to the tune of a 2.07 ERA and a 102:19 K:BB ratio in 95.2 innings.
This year, Cole has spent the season back in High-A, this time in the Carolina League. Once again, his High-A ERA isn't pretty (4.43), but he has generally pitched better than that number would indicate. In 91.1 innings, Cole has struck-out 99 while walking 22. His HR/9 is high, however, having allowed 11 homeruns. Cole pitched in the All-Star Futures Game this week and earned the save for Team USA. He is likely to finish the year in High-A and make his Double-A debut next season as a 22-year-old.
Status: Back home again
The 2012 season was a forgettable one for Choice, who struggled for the first part of the season, found his groove in June and then saw his season end abruptly six weeks early with a broken hand. Choice wasn't able to play winter ball, so he came into the 2013 season with nearly seven months away from live game action. Normally a slow starter, Choice had a strong spring training in big league camp and then carried that over into his first month at the Triple-A level. He posted an 873 OPS in April and has put together a solid season for the River Cats. In 90 games, he has a .292/.383/.430 line with 11 homeruns.
Choice will be starting in the Triple-A All-Star game later this week. He has been one of the most consistent hitters on the River Cats' roster this season. Choice hasn't hit lower than .279 in any one month and he has had a .355 OBP or higher in each month. Choice's power numbers were down in June and the start of July, but his average has been up during that stretch. He has shown the ability to take what the opposing pitchers are giving him this season, using all fields to get on-base even when they are pitching away from his power-hitting ‘zones.
Choice has always put up prodigious strike-out totals, but his strike-out rate is down slightly and his walk rate is up nearly three percent over last year. Choice has been primarily a centerfielder during his pro career, but he has seen time in both corner positions this season. Should the A's incur another injury in the outfield this season or decide to bring up extra reinforcements in September, Choice should be at the top of their list of options. He will need to be added to the A's 40-man roster this off-season and, with Seth Smith, Chris Young and Coco Crisp all possible free agents this off-season, Choice is putting himself in good position to compete for a big league roster spot next spring.
Status: PCL All-Star
2. Dan Straily
Only the Capitol Corridor Amtrak train has made more trips between Oakland and Sacramento this season than Straily. The A's on-again, off-again fifth starter has had three stints each in Sacramento and Oakland this season. Currently back with the River Cats so he could stay on turn while the A's don't need a fifth starter, Straily is expected to return to the A's in a week.
Although he has had his ups-and-downs, Straily has put together a pretty good season with the A's, all things considered. He has 14 big league starts under his belt this year. In those 80 innings, Straily is 6-2 with a 4.28 ERA and a 66:26 K:BB ratio. Straily has allowed seven homeruns, but all but one of those came in his four worst starts of the season. Early in the year, he had a difficult time going late into games because of high pitch counts, but he has been much more efficient with his pitches over the past two-and-a-half months. Overall, Straily has improved his H/9, HR/9, BB/9 and K/9 over his big league time last season.
During his minor league stints, Straily has continued to dominate. In 31.2 innings, he has a 33:9 K:BB ratio and a 1.14 ERA. There isn't much left for Straily to learn in the minor leagues, but he may continue to go back-and-forth between the two levels this year as the A's make adjustments with their rotation. Nonetheless, he should be an important player for the A's down-the-stretch. With Bartolo Colon a pending free agent, Straily is in a strong position to be part of the A's standard five-man rotation in 2014.
Status:, Riding the Sac-Oak shuttle
1. Addison Russell
It seemed like Russell was incapable of doing anything but dominate last season, so when he got off to a bit of a slow start with the High-A Stockton Ports this year, there was some cause for concern amongst A's fans. There was little concern within the organization, however, as the A's coaches and front office personnel were confident that Russell would find his way in the Cal League and soon begin to dominate once again. They were right.
At the end of May, Russell's OPS stool firmly in the 700s and his batting average was hovering close to the Mendoza line. Since then, Russell has raised his overall line to .263/.341/.478. He has nine homers and 12 stolen bases in 77 games. At 19 years old, Russell has been one of the youngest players in the Cal League all season. Despite playing against competition mostly three to four years his elder, Russell ranks 23rd in the league in OPS and 20th in SLG.
Defensively, Russell has looked smooth at shortstop, showing good range and the ability to make the acrobatic play. He has occasionally struggled with long throws, although it appears those struggles have been related more to footwork than arm strength. Russell's strike-out totals are high (91 in 77 games), but high strike-out totals are hardly uncommon in the Cal League, where hitters tend to be aggressive.
Russell has shown poise and maturity well beyond his years this season, never letting his slow start get into his head. The last 19-year-old phenom the A's had make his first full season at the High-A level was Eric Chavez. Russell is thus far out-performing Chavez's 1997 season with Visalia. Russell will likely remain in the Cal League for the rest of the season, although the A's could give him a taste of Double-A at the end of the year if the Ports are out of the post-season hunt.
Status: Playing beyond his years