The Rangers have promoted two pitchers from their minor league ranks to fill openings in the big league rotation.  Familiar fantasy face, Roy Oswalt, is one of the two.  The other is 23-year-old Justin Grimm, who debuted last week and was rather effective.  Grimm was having a nice campaign in Double-A — nothing eye-popping, but he was among the most efficient pitchers in the Texas League, which is surely why the Rangers are giving him a look.  I’m not so sure he’s worth the same look in the fantasy game, however.  He’s slotted to throw twice next week, so if you’re two-start streaming… whatever.  But he’s hardly rosterable outside of AL-Only formats.  What’s interesting to note here is that Grimm leaped over the Rangers’ top pitching prospect Martin Perez.  Perez had been having a lousy year in the PCL, so it’s not necessarily surprising that Grimm was given the nod, but the move seems to have ignited Perez.  He’s surrendered only two runs through his last two outings, one of those being a complete game (only 90 pitches, too).  Featuring a plus fastball with sneaky velocity, a plus-plus change, and a sharp curve, Perez has frontline stuff.  It’s hard to say how long the Rangers will have room for either Grimm or another arm, but if Perez continues this recent hot streak, I’m confident he’ll supplant Grimm.  Should that scenario come to pass, add Perez in all formats.

Drew Pomeranz | LHP, Colorado — Pomeranz has been pretty bad in Triple-A.  Some of that needs to be attributed to the park he plays in, but it’s mostly due to sloppy pitching, if you ask me.  His most recent outing, though, was by far his best this year.  Pomeranz pitched six no-hit innings on Tuesday, walking three and whiffing eight in the process.  He has one of the meanest curves in the game, but injuries have been holding him back.  Huge potential to dominate minor league hitters and get back to the bigs if he can get rolling.

Trevor Bauer | RHP, D’Backs — So, Joe Saunders has a bum shoulder and the whole world is wondering if this will mark the coming of Bauer.  Certainly seems plausible.  Meanwhile, Bauer continues to struggle with command, walking four in his last outing.

Danny Hultzen | LHP, MarinersHultz got the bump to Triple-A, so I guess he’s not skipping that level.  I’ve been sticking to my late-July ETA, and I’ll continue to do so.  A month or so in the PCL seems about right.

Billy Hamilton | SS, RedsHamilton’s stolen, like, 8,000 bases or something now.  Earlier in the week, he was robbed at gunpoint in what must’ve been a frightening ordeal.  Insert overplayed karma joke.

Josh Vitters | 3B, CubsShould you still believe in Josh Vitters?  Probably not.  But the former 1st-round selection is having something of a bounce back year at Triple-A Iowa.  Hitting .385/.442/.641 over his last 10 games, Vitters appears to be comfortable and confident at the plate — something we haven’t seen out of him since 2009.

Ryan Lavarnway | C, Red Sox — Lavarnway’s power production is down, but his approach seems improved as he has elevated his OBP to just a tick beneath .400.  The Red Sox, who aren’t in need of catcher help at the moment, could dangle Lavarnway as trade bait over the next couple months.

Kaleb Cowart | 3B, Angels Cowart opened the year as one of the more advanced hitters in the Midwest League, and he backed up that perception by hitting .293/.348/.479 with 9 HR in 66 games.  The Angels promoted Cowart to High-A Inland Empire this past week.  Look for his power numbers to increase in the hitter-friendly environment of the Cali League.

Gary Sanchez | C, Yankees After an up-and-down year in the South Atlantic League in 2011, the Yankees sent Sanchez back to repeat the level for 2012.  Results thus far are much improved:  .315/.362/.549 with 31 XBH in 254 PA.  Sanchez is one of the top catching prospects left in the minors, and it only appears that his stock is rising.

Shelby Miller | RHP, Cardinals The Cardinals are having Miller skip his next start in order to work on mechanics.  The highly-touted pitching prospect has struggled mightily in Triple-A during recent weeks.

Andrew Chafin | LHP, D’Backs — I recently said nice things about Chafin here and here.  Well, through his last two outings he’s surrendered 15 ER while walking 9.  The Razzball kiss of death in full effect, baby.