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Oakland SS Addison Russell is yet another big name with draft pedigree for Mesa, going 11th overall in the 2012 draft out of a Florida panhandle high school. He's had a notable pro career, turning late momentum with the bat from his senior season in high school to a super productive minor league career, putting up big numbers and spending his whole age-19 season at Hi-A and hitting well: .275/.377/.508. Clubs normally send players to the AFL either 1) to get reps after an injury-shortened season or 2) to get reps because they may be going from the lower minors to the big leagues quickly and this would speed the process. It's clearly the latter with Russell.
Russell is a little tough to peg offensively as he's changed his approach and body a few times in the last few years and is the type of hitter that is so talented he can chose what kind of hitter he wants to be. I've seen him do the hyper-agressive pull-happy power thing, the super-patient late count hitter that hits mistakes and the well-balanced, all-field threat, with the latter being what he's settling in as now. As you can see in the above video, his first move with his hands is down, which is normally a terrible indicator for contact, as it lengthens a swing and normally leads to other bad habits, but Russell has enough bat speed and feel to hit to make it work. He faced super-premium velocity in the week I saw him from Alex Meyer and Aaron Sanchez and handled it as well as could be expected.
Russell has above average raw power to all fields that plays closer to average in games but was plus in the past when he was 20-30 pounds heavier, so anywhere from 15-25 homers is possible at maturity, though I'd bank on the low end of that range. I think he'll get his fair share of walks and strikeouts, hit in the .270s, be about average defensively at shortstop (solid-average arm, good actions and footwork) and use his above average to plus speed on the bases when necessary.
Angels 2B Taylor Lindsey went in the sandwich round out of high school in 2010 but isn't nearly the prospect Russell is. Lindsey has one standout tool that could carry him to a solid big league career. He's limited to second base and is only a solid-average runner but his 40 raw power that he shows in BP plays up a notch in the game with a little more effort. Lindsey doesn't have elite bat speed or bat control but makes the most out of his line drive bat path and simple mechanics. He has a chance to hit .270 or .280 with 10-12 homers, which could make him one of the top 30 second basemen in the game at some point.
There were three other middle infielders on Mesa that all ranked behind Russell and Lindsey for me: Cubs 2B Wes Darvill, Tigers SS Dixon Machado and Tigers 2B Devon Travis. I didn't see Darvill play in a game, but he was fine defensively in infield, had below average power in BP and a solid lefty stroke but swung like he was had more power than he did. I can't crush him on this look but I saw him briefly before the AFL and have him as an upper minors fill type. Machado can play a fringy to average big league shortstop and has some bat speed, but can't quite put it together at the plate. He has a little raw power but is overmatched by better stuff as his approach is just okay and injuries have kept him from getting the necessary ABs to improve. Machado will be just 22 in 2014 and has been promoted before his bat's been ready for each level due to his glove, but I'm not sure it's going to catch up.
It's easy to count out Travis somewhat once you see him as he's backed into a corner profile-wise as a 5'9/180, right-handed hitting second baseman. Travis has as little power as you think but plays an excellent second base and while I only saw one game from him and didn't get a good look at his speed, he looked like an above average runner. Travis has a good sense of the strike zone and made hard contact on the three game swings I saw, with excellent triple-slash and plate discipline numbers against lower level competition in 2013. He'll be challenged in 2014 at age 23 in AA after raking at Lo-A and Hi-A in 2013 (.351/.418/.518 combined line) and will have a chance to prove if he can carve out a niche as an energetic bench type.