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Oakland A's top-50 prospects mid-season review: 30-21

During the off-season, we named our top-50 prospects in the Oakland A's system. Now that we have passed the midway point of the season, we thought it would be a good time to check the progress of those players. In the third in our series, we take a look at the progress of prospects 30-21 from our off-season list.

Note: this is not a re-ranking of current prospects. A new top-50 prospects list will be released this off-season. To view our preseason top-50 Oakland A's prospects list, click here.

Stats as of 7/17/16

30) Jesus Lopez, IF Lopez had been on an aggressive track, making his full-season debut this year as a 19-year-old. The switch-hitting middle infielder has never put up big numbers in his brief professional career, but he has continually played well during camp settings, such as spring training, Instructional League and extended spring. This year was no exception, as Lopez played his way onto the Beloit Snappers’ Opening Day roster after a strong spring. He never got going with the Snappers, hitting .190 in 56 games before being sent back to Vermont, where he is four for his first 26.

Lopez has the talent to be an above-average hitter as a middle infielder. He has a pretty swing from both sides of the plate and the ability to drive the ball in the gaps. Lopez runs well and has the tools to be a top-of-the-order hitter. He is still learning pitch recognition and will take his lumps until that improves. Defensively, he has played well at second, short and third this year. He is versatile enough to continue to develop at all three positions.

Lopez will likely spend the rest of the season with Vermont. He should get another shot at the Midwest League next year, in his age-20 season.

Status: Looking to get on track

29) Tucker Healy, RHP Ryon Healy isn’t the only Healy making noise in the Oakland A’s system this season. Tucker has been arguably the best reliever on the Triple-A Nashville roster in 2016. It seems only a matter of time before he gets an opportunity to pitch in the big leagues. In 36.1 innings for the Sounds, Healy has a 2.72 ERA and a 53:15 K:BB. He has allowed just two homeruns and opposing batters are hitting .192 against him. 

Healy offers plenty of deception with his throwing motion and can get his fastball up to 95 and sits 92-93. He struggled during his first taste of Triple-A baseball in 2014 and spent the entire 2015 season in Double-A working on fastball command. That area of his game has improved considerably and has led to much better results in his return to Triple-A. His fastball gets plenty of late movement, often disappearing on hitters just as it reaches the plate. Healy also features a solid change-up and an improving breaking ball.

Healy has yet to get the call to Oakland despite the A’s frequent use of the Nashville bullpen. However, with every day that Healy continues to dominate at Triple-A, it becomes more and more likely that he will reach the big leagues by the end of this season. 

Status: Dominating the PCL

28) Chris Kohler, LHP It has been a lost three seasons for the talented Kohler, who missed all of the 2014 season with injury and will miss all of this season after undergoing left shoulder surgery early in the year. Since turning pro in 2013, Kohler has thrown only 61.1 innings.

Kohler didn’t have his best stuff last season, so it wasn’t a complete surprise when he ended up with an injury in 2016. He is scheduled to start throwing again soon now that he is three months out from the surgery and should be back on the mound by next spring. The A’s will be careful with the young lefty, who is still just 21. If Kohler isn’t able to get his arm healthy, he could return as a hitter, as he was an accomplished middle of the order bat in high school and a number of teams scouted him as a position player.

Status: On the disabled list

27) Jesus Zambrano, RHP Zambrano opened a lot of eyes last season when the A’s called on him to make two starts in Triple-A as an 18-year-old. Zambrano continued to show he was mature beyond his years with a strong showing as a starter in the highly competitive Venezuelan Winter League. The right-hander began this year on the Low-A Beloit Snappers roster as part of the Snappers’ tandem rotation. Zambrano struggled from the outset, however, and spent nearly a month on the disabled list with a dead arm. The A’s sent him back to short-season Vermont after he posted a 7.04 ERA in 23 innings with Beloit. Zambrano continued to struggle when he first got to Vermont, but he has put together a couple of solid outings in a row and has a 3.71 ERA in 17 innings.

Zambrano relies on touch and command to be effective and he hasn’t had much of either this season. Everything has been up in the strike-zone, and Zambrano doesn’t have the velocity to get away with pitching up. The A’s feel he has been pitching tired all season after he threw all winter. He will be limited to shorter outings with plenty of rest in-between for the remainder of this season, as the A’s try to allow him to continue to work on his command while not taxing him much further.

Zambrano will likely finish off the season with Vermont and should have another chance to pitch in the Beloit rotation next season, hopefully with a fresher arm. He won’t turn 20 until late August, so he is still young for the level.

Status: Working through command issues

26) Oscar Tovar, RHP Tovar was the talk of the A’s fall Instructional League, even though he threw only limited innings in “official” Instructs games. It was hard not to get excited about the young right-hander, who touched 96 with ease and flashed two promising secondary pitches – a change-up and a breaking ball. Tovar spent the spring at extended spring training and was expected to open the year on the AZL A’s roster. That ended up being delayed when he was popped for violating minor league baseball’s drug policy. He finished his suspension on July 4 and he made his debut on July 5.

Tovar has thrown only 10 innings thus far, and he has allowed 12 hits and four walks. However, he has shown better location at times than those numbers would indicate and the stuff has been electric. There will be a learning curve for the 18-year-old, but Tovar has all of the makings of a premier pitching prospect. 

He will remain in Arizona the rest of the season and is likely to make-up for some of his lost inning at both of the A’s fall Instructional Leagues.

Status: Getting his feet wet in the AZL 

25) Zack Erwin, LHP Erwin has had a whirlwind last 12 months, as he went from the Chicago White Sox’s 2015 fourth-round pick to a member of the Oakland A’s in an off-season trade. Erwin jumped to High-A to start the 2016 season and he has remained all season on the Stockton Ports’ pitching staff. The left-hander has struggled in the hitter-friendly Cal League, posting a 6.53 ERA in 80 innings. He has struck-out 58 and walked 32 and has allowed 11 homeruns.

The Cal League was a challenge assignment for Erwin, who threw only 40.1 innings in pro ball last season – with just 19.1 of them coming in Low-A. The A’s felt Erwin was polished enough to handle the challenge, and he has looked like he can handle the level at times, but has been very hittable in other outings. Erwin’s velocity has been a little down compared to last year, as well, which is likely contributing to his struggles.

Erwin’s struggles are reminiscent of the struggles that former college teammate Daniel Gossett had in his first full pro season last year. The A’s are hopeful he can have a rebound 2017 season much like Gossett has rebounded in 2016.

Status: Battling inconsistency with Stockton

24) Sandber Pimentel, 1B Pimentel is another young player the A’s have moved aggressively. He made his US debut last season in Low-A, skipping over both US short-season leagues. Pimentel had an up-and-down year with the Snappers in 2015, but he still finished with 13 homers in a pitcher-friendly league. The A’s pushed Pimentel up a level in 2016, and he has put together a solid season with the Stockton Ports. Going into Monday’s game, Pimentel was batting .241/.335/.453 with 14 homers in 78 games.

There is a lot to like about Pimentel’s game. He has above-average power to all fields and has an idea of what he wants to do at the plate. Pimentel swings-and-misses a fair amount, but he also works the count well and can still do damage in pitcher’s counts. Defensively, he is prone to the lapse in concentration, but he moves surprisingly well for a player his size and has some range as well as soft hands. Pimentel is still learning the nuances of competing at an advanced level day-in and day-out, but he has shown growth over last year. He isn’t quite as athletic and doesn’t have his throwing arm, but Pimentel has many similar qualities to fellow A’s prospect Matt Olson.

Pimentel will remain in Stockton the rest of this season and, if he continues to play as he has thus far this season, will be in a strong position to be in Double-A for his age-22 season. 

Status: Hitting for power in the Cal League

23) Ryan Dull, RHP Dull rose from relative obscurity last season, pitching his way out of a logjam in Double-A all the way to the big leagues. He finished the year with a very solid September in Oakland and positioned himself for a spot on the A’s big league roster in 2016. Dull didn’t let his opportunity with the A’s pass him by during the spring. He was one of the A’s top pitchers in camp and easily earned a role in the A’s bullpen. Since then, he has worked his way from middle reliever to set-up man and even set a record for most consecutive runners stranded to start a season along the way. On Monday, Dull allowed an earned run for the first time since June 18. His ERA still sits at 2.05 in 48.1 innings. He has 50 strike-outs and only 10 walks.

Dull doesn’t have traditional closer stuff, but he may be the A’s closer of the future. He relies on fastball movement and a good slider to keep hitters from getting good swings on him. Dull is fearless on the mound and never panics, a mentality that serves him well late in games.

Less than a year from riding the busses in the Texas League, Dull is now a fixture in the A’s bullpen. He should continue to play an important role for Oakland throughout this season.

Status: Pitching well in the big leagues

22) Dustin Driver, RHP It has no doubt been a frustrating past two seasons for Driver, who has entered each season with high expectations but has struggled to command his pitches and has been hit hard as a result. This season, Driver has pitched mostly in Low-A Beloit, save for two appearances in Vermont. His ERA for the season is 8.37 and he has an 18:26 K:BB in 23.2 innings. He also missed six weeks on the DL with elbow discomfort.

Driver can hit the high-90s with his fastball and he has the makings of a promising slider and change-up. Right now, he isn’t throwing any of his pitches with a lot of confidence. The A’s are trying to simplify the game for him right now and have him focus just on fastball command as a reliever. They hope to improve that aspect of his game first and then build up the rest. He won’t turn 22 until after the season, so Driver has time to work out the wrinkles and still be a major league pitcher.

Driver will likely continue to pitch in short stints for Beloit for the remainder of this season and will continue to work on his arsenal this fall during Instructs.

Status: Searching for his command in Low-A

21) R.J. Alvarez, RHP The A’s had high hopes for Alvarez when they acquired him from San Diego as part of the Derek Norris deal. Alvarez zoomed through the minor leagues with the Angels and the Padres, reaching the big leagues during his second full pro season. The hard-throwing reliever put up ridiculous strike-out numbers in the minors and continued to do so with Triple-A Nashville in 2015 with the A’s. His command issues made him hittable at the big league level despite his high-90s fastball and sharp slider. He had a 9.90 ERA in 20 innings with the A’s.

This spring, Alvarez came into camp with a chance to make the A’s Opening Day roster, but he struggled and was shut down with a sore elbow that required surgery to remove bone chips. Alvarez began his rehab with the Stockton Ports on June 3 and then joined the Sounds on June 9th. Alvarez made only one appearance for the Sounds and then was surprisingly placed on waivers. The Chicago Cubs claimed him and he has been pitching in Double-A for Chicago since then. Alvarez has struggled, allowing 17 hits and six walks in nine innings (8.00 ERA).  

Alvarez is still young and has the kind of stuff that plays well late in big league games, but his command will need to improve to get another shot at the big leagues.

Status: Trying to regain his control with Cubs

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