Ty Buttrey, RHP
Buttrey's season began in early May, but not well, as he lasted all of two-thirds of an inning before he was listed after allowing four runs, three of them earned. He recovered in his most recent start, pitching 4-2/3 one-run frames but with three walks against three strikeouts. You might feel like you've been hearing Buttrey's name forever since he was a 2012 draft pick, but remember that he was selected out of high school and is just now getting to full-season ball for the first time in his career: there are going to be bumps in the road when you're 21, without college experience, and coming into the year with fewer than 70 innings pitched in the pros.
He's already got the pitcher body despite his youth, at 6-foot-6 and 230 pounds, but he's obviously still very raw as an actual pitcher. He's missing bats and inducing more ground balls than fly balls in the early going, but he'll need to reduce his walk rate while figuring out how to throw consistent, quality strikes against Low-A hitters before we can expect much more.
Tzu-Wei Lin, SS
Lin started off well, but has seen his numbers drop considerably. He's in the midst of a poor 10-game stretch in which he's batting .225/.333/.300, with almost all of that on-base percentage coming in his last two games, where he's managed to walk five times. He's not striking out overly much, just around 16 percent, but he still can't get his batting average on balls in play up to low-minors standards. At least he's cut into his strikeouts to this point, dropping from last season's 23 percent.
He's a defense-first shortstop expected to draw walks and hit singles, but so far, only the walks are coming. As he faces more experienced pitchers, those will start to vanish unless he begins to put the ball in play effectively more often. He's still all of 20 years old, however, so don't take that as some kind of urgent need.
Carlos Asuaje, 3B
Asuaje was Boston's 11th-round pick in the 2013 draft, and to this point, he's looking like an excellent selection. He's spent time all over the diamond, with three games in left, five at designated hitter, six at second, and 17 at third base, which seems to be his primary position since he was drafted. He's stepped up on last year's solid .269/.366/.368 effort at short-season Lowell by mashing Low-A pitching, with 20 extra-base hits in 31 games and an Isolated Power approaching .300.
Let's not get too carried away, though. Asuaje was compared to the Cardinals' Kolten Wong for his bat speed, defense, and legs, but also was expected to have less power, and Wong doesn't have all that much to begin with. That's not to say the comp was 100 percent accurate, but we'll need more than 31 games against low-level pitching to figure out what this 22-year-old is capable of. If you need more of a reminder of that, recall the performance of Bryce Brentz -- who legitimately does have power -- at Greenville. Back when he was 22, he batted .359/.414/.647 for 40 games before getting a bump to Salem. While he kept hitting there, it wasn't quite to that degree, and he's seen his performance drop with each new challenge.
Asuaje looks more disciplined than Brentz, and isn't expected to have the same kind of holes in his swing, so it's not a perfect comparison obviously. It's just worth remembering that getting overly excited about small samples in the low levels of the minors will burn you more often than you'd like. Asuaje might turn out to be a complete steal, but it will take more than a few dozen games in Greenville to know. Like with Brentz, we might not see Boston wait for their typical 60ish games or the Sally's All-Star game to promote Asuaje, knowing that new challenges are the only way to figure out what he is rather than more games at a level he's clearly conquered.