Rex Brothers, LHP, Rockies
A supplemental first-round pick in 2009, Brothers pitched well at High- and Double-A last year and was lined up for a possible September look this season. That's a swift timetable as it is, but Brothers has hastened the pace this spring buy firing six shutout innings, including three straight perfect appearances while striking out six of the nine batters he faced. With a mid-90s fastball and killer slider, Brothers has always had late inning stuff, and if he is able to maintain his sudden ability to consistently throw strikes, he'll not only break camp in the big leagues, but will pitch some high-leverage innings as well.
Dan Descalso, 2B, Cardinals
Skip Schumaker has been plenty good this spring, leaving Descalso destined for a third year at Triple-A; at least the Cardinals now know they have a good back-up plan. He's not especially big or toolsy, but Descalso can hit, and with a six-for-ten weekend, he's now at .341/.386/.488 in the exhibition season. Despite this, his chance might not come until he changes teams, as Schumaker is one of Tony Larussa's favorites, and in the end, Descalso might not be much more than another version of the same as opposed to an obvious upgrade.
Matt Dominguez, 3B, Marlins
The Marlins may have wanted Dominguez to win the third base job this spring, but not all wishes come true, as after homering and driving in five 12 days ago, Dominguez has fallen into a 1-for-25 slump, dropping his exhibition averages to .175/.267/.350. The Marlins’ hope that a player coming off a .252/.333/.411 season as 20-year-old at Double-A would prove himself to be big league ready was wishcasting in the first place. Dominguez is still a potential Gold Glove winner, the team's top prospect, and its third baseman of the future. It's just going to take a little longer.
Tyler Flowers, C, White Sox
Flowers is hitting .500 this spring (9-for-18), and one has to wonder if the White Sox aren't just a little bit annoyed about it. The plan had been for Flowers to take over big league catching from A.J. Pierzynski once the latter’s contract expired with the 2010 season, but with a .220/.334/.434 showing at Triple-A last year and scouts mumbling about regression on both offense and defense, the White Sox opted to bring back the veteran. Flowers will head back to Triple-A for the third straight year, but he could have some value in the trade market come July.
Sonny Gray, RHP, Vanderbilt
Gray struck out 10 over 7 1/3 shutout innings on Friday, but it wasn't even close to his best start of the year. On a statistical level, he's been nothing short of awesome, striking out 46 over 33 2/3 innings while limiting opposing hitters to a .140 batting average and just two extra base hits. On a stuff level, it's all there as well, as he sits in the low-to-mid 90s with an electric fastball , and that's not even his best pitch—his knee-buckling power curve earning plenty of 70 grades from scouts. Still, Gray might not even be a top-10 pick, as he's less than six feet tall, and the effort it takes for his frame to produce power stuff leads to some not unexpected command and control problems. Some scouting directors see him as a starter, others as (potentially) a right-handed Billy Wagner in the back of a bullpen. It’s that debate which could cause others with lesser stuff and performance to go ahead of him come June.
Devin Mesoraco, C, Reds
A first-round pick in 2007, Mesoraco was on the brink of being labeled a bust as the 2010 season began, but suddenly hit .302/.377/.587 with scouting reports nearly as impressive as the numbers themselves. Now, it's time to prove it's for real, and Mesoraco has been doing just that this spring, going 3-for-4 with a pair of doubles over the weekend to raise his spring average to .462 (12-for-26). His emergence makes the Reds rich in backstops, with 2010 first-round pick Yasmani Grandal not far behind Mesoraco, and could give them a rare big league trade chip come July with a more-than-capable Ramon Hernandez becoming available in a market filled with playoff teams short behind the plate. This potential win-win situation is why up-the-middle talent is so important at every level.
Peter O'Brien, C, Bethune-Cookman
While the 2011 draft class is potentially historic, one of its weaknesses is catching. O'Brien began the year as the top college backstop in the board and a potential late first-round pick, but the significant holes in his game have become glaring at times. He's hitting just .265 in 22 games while continuing to earn below-average grades for his defense. The good news is that with home runs on Friday and Saturday, he now has six in 83 at-bats, giving him the kind of power numbers that are suddenly hard to find with the new college bat rules. Whether that tool alone will be enough to get him into the seven-figure bonus area is still up for debate, but it's not only chicks that dig the long ball—scouting directors do as well.
Mark Prior, RHP, Yankees
Sure he's not a prospect anymore, but he's a honorary one for this list, as he hasn't stood on a big league mound since August 10th, 2006 and is well into starting-over mode. Having signed with the first team to draft him (1998) in the off-season, Prior has pitched sparingly but well, striking out eight over 5 2/3 innings while surrendering just one earned run. The stuff is long gone, and Prior is trying to get by on his ability to locate and add spin to a 88-92 mph fastball, but you have to give it to a guy that could have walked away eons ago with nothing to be ashamed of. There's some talk that Joba Chamberlain's injury could open the big league door for Prior, but more realistically, he'll need to prove he can keep fooling them at Triple-A for awhile.
Tyler Skaggs, LHP, Diamondbacks
The key prospect received from the Angels in the Dan Haren deal, Skaggs was the extra guy in Sunday's split-season game against Oakland, and was more than impressive in his first appearance with the big-league club, firing three shutout innings while striking out four. Just 19 years old, Skaggs is still very much a work in progress, but with both his command and curveball already above-average, he has the rare ability to get hitters out now while still providing plenty to dream on. With a lanky six-foot-four frame and long levers, scouts think he possesses more than the average velocity he shows now, and if that manifests, his stock could soar.
Mason Tobin, RHP, Rangers
Plenty of rule five picks have already been returned, but Tobin is still in Texas, and with several members of the anticipated big-league bullpen putting up brutal numbers this spring, his chances are better than ever. A massive flyer who has pitched to just 14 batters over the past two years due to Tommy John surgery and a later clean-up procedure, Tobin hasn't been nearly as good as his 0.00 ERA; he's allowed four hits and three walks in 5 2/3 innings, but he's earning praise for a heavy 90-95 mph two-seam fastball, and a good changeup, although his slider remains below average. Seen as one of the biggest long shots immediately after the rule five draft in December, he's suddenly among the most likely to stick.