Bryce Brentz, RF
Brentz's line over the last 10 days is looking good at .324/.375/.568, but that's almost entirely from his May 31 game against Harrisburg, in which he went 5-for-5 with three doubles. Cut that out from under him, and leave things in June, and you've got a .219/.286/.406 stretch with 14 strikeouts in 35 chances.
Of course, that's not really who Brentz is, no more so than his perfect night at the plate was. It's simply a reminder that, for all the progress he made in the month of May, cutting down on his strikeouts a bit and posting an OPS over 1000, Brentz is still a 23-year-old learning how to adjust to the pitchers of Double-A. Sometimes, there are going to be stretches where his over-aggressive nature results in the occasional bomb -- five of his seven hits in June are of the extra-base variety -- but more often than not, ends with a dejected look and a walk back to the dugout after striking nothing but the air in front of him.
Brentz's stock hasn't changed much at all during the 2012 season. There are still questions about his approach, as well as the holes in his swing. More of May would go a long way towards remedying the issues and the nervousness surrounding them, and it's likely he'll have all of the 2012 season to do it. When he's hit so well for so long at Double-A that he's more likely to create bad habits than he is to learn anything, he'll get a promotion to Pawtucket, but he's only looked like that briefly in the season's two-and-a-half months.
Oscar Tejeda, LF
Tejeda is finally back from the disabled list, after last playing on May 15. His absence didn't cause him to forget where he left off, though, as he's hit all of .156/.206/.281 in 32 at-bats and eight games since his return. May had started to look decent for Tejeda, at least in terms of power, but he's shown no progress on the plate discipline front, nor in his ability to control a plate appearance.
He's all of 22, but this is his second stint at the level, and after a move to the outfield from second base, you'd like to see more out of him at the plate. The tools are there, as they've always been, but seeing them translate into production and results would do wonders for the righty.
Part of the reason for the impatience on this end is that he's taking up a precious 40-man roster spot, but hasn't hit a lick since he was 20 years old and in High-A back in 2010. He's still showing middle infield pop, but this time while playing in a corner outfield spot and as a designated hitter.
Without any real and lasting adjustments made in his game, Tejeda's ceiling isn't getting any higher as time goes by. It's starting to look like he's not going to be the kind of player who would crack Boston's lineup, were he to make it to that level, and given his placement on the 40-man roster, that might mean he's likely to be dealt this summer, in the same way Yamaico Navarro was sent to a club that could roll the dice on him. You always prefer your prospects pan out, but when they're as frustrating as Tejeda, sometimes it's worth seeing how much someone else values them.
Juan Carlos Linares, OF
Linares has been doing well for Double-A Portland, striking out very little, walking a bit, and hitting for plenty of average and power. There are obvious caveats you don't need pointed out to you, though, such as the fact he's 27 years old, and this is a league full of far younger opponents. That's not to say it's all a mirage, though: it's just that we don't really know what it is yet.
Linares played briefly for Pawtucket in 2011 before injuries ended his campaign, and if not for the logjam of outfielders on the Triple-A roster to begin the year, likely would have had a second chance at the level in 2012. Instead, he had his attempt at playing every day take place in Double-A Portland, and the results have been solid.
It's tempting to assume that Linares would just hit at Triple-A and in the majors because he's doing well at Double-A in his first full taste of American baseball, but that's not how this works. Not every single player who is old for his level and succeeds is Daniel Nava: part of the reason Nava is special is because he's closer to unique in those respects than he is part of a trend.
That's not to say Boston shouldn't toss Linares into Triple-A again at some point and see what his deal is. It's just important to remember that a guy belting Double-A fastballs -- and either struggling against or ignoring much of the other offerings -- isn't necessarily someone who is going to dominate at all levels. It's much easier for a good fastball hitter to excel at a level where advanced secondary offerings aren't everywhere you look, and until he starts to produce against good, non-fastballs consistently, it's hard to assume that his power is going to stick against tougher competition. He's hit well enough to have the chance to fail, though, and with any luck, Boston will give him the bump back to Triple-A before too much longer.