Brown, Ackley could soon follow Hosmer as impact call-ups

The Royals are setting a speedy early pace in the prospect-promotion game in 2011, having called up first baseman Eric Hosmer two weeks ago and lefthanded pitcher Danny Duffy to make his major league debut with a start tonight. Other hot prospects, such as the Giants' Brandon Belt and the Braves' Julio Teheran, have made big-league cameos but will soon be clamoring for an extended audition.

Late May and early June is often a fertile time for clubs to summon their top prospects, as they try to deftly avoid giving their future stars Super Two status, meaning they'd be eligible for four years of arbitration instead of three, costing millions more in payroll. That designation is granted to the top 17 percent of players in service time each year who have more than two years of service time but fewer than three. In general teams are safe promoting players Memorial Day weekend or later.

Injuries in the big leagues can always accelerate a club's preferred timetable, but barring those, herewith are a baker's dozen of top prospects biding their time for a major league call-up and worth stashing on your fan (or fantasy) radar.

Each of these players is expected to play either a big role for his team this season or at least a spot role on a club likely to contend for a playoff spot. So if you're looking for some of the game's brightest but youngest prospects -- such as the Nationals' Bryce Harper, currently tearing up Single-A pitching, or the Angels' Mike Trout, currently doing likewise in Double-A -- you'll almost certainly have to wait until the 2012 edition of this list. Those below are ordered based on predicted impact, which combines early promotion date and expected performance upon their arrival.

NOTE: All stats are updated through Monday, May 17.

Domonic Brown, Phillies RF

A pair of injuries to his right hand -- a hamate bone broken in spring training and a thumb sprained last week -- have conspired to slow Brown's inevitable promotion to the majors. Nothing else can. In 14 games split between High Class A Clearwater and Triple-A Lehigh Valley, Brown has batted .358 with a .426 on-base percentage and .642 slugging percentage. He's homered four times in 53 at bats, but the thumb injury will keep him sidelined until probably the weekend.

Baseball America's preseason No. 4 prospect in the game, Brown is a true five-tool stud who will provide some needed offense to Philadelphia's corner outfield positions. The wiry strong and blazing fast Brown, who was offered a football scholarship to play wide receiver at Miami, could help spell underperforming leftfielder Raul Ibañez (.618 OPS) and relegate rightfielder Ben Francisco (.692 OPS) to the super-sub role he's best suited for.

Brown's 2010 major league stats are deceiving. He batted .210 with two homers in 62 at bats, but with Jayson Werth still on the team, Brown was reduced to a pinch-hitting role he was not accustomed to and was hampered by a few nagging aches and pains. But there is no doubt the 23-year-old Brown will be a star and the Phillies, who are in the rare position of having a below-average offense (19th in runs scored), could use him sooner rather than later.

Dustin Ackley, Mariners 2B

The Mariners drafted Ackley No. 2 overall in 2009 and swiftly installed him at second base, despite him primarily playing first base and outfield at the University of North Carolina. Such a defensive adjustment doesn't happen overnight, but Ackley has made progress. And his swing has always been pure -- rarely more so than the past nine games, in which he has multiple hits in six of them, going 16-for-36 (.444).

He began 2010, his first minor league season, in Double-A and then worked his way to Triple-A for 52 games, batting .274 with a .338 OBP, five home runs and 20 walks. In his first 39 games of Triple-A in 2011 Ackley has already matched his total of five homers and exceeded his walks total with 33, while hitting .270 but now with a .394 OBP and also stealing six bases. He can't cure Seattle's need for a middle-of-the-order thumper, but he can certainly hit better than the current second basemen, Adam Kennedy and Jack Wilson.

Mike Moustakas, Royals 3B

The betting man would have wagered this winter that Moustakas, not Hosmer, would have been the first of Kansas City's blue-chip prospects to reach the majors, but Moose may not be far behind. Moustakas, who at 22 is one year older than Hosmer, crushed 36 home runs last year while splitting his season between Double-A and Triple-A, tying him for the most of any player in the minor leagues. And he's not an all-or-nothing power guy: He batted .322 and added 41 doubles.

The primary reasons Hosmer got the first call were that he was hitting .439 and that big-league first baseman Kila Ka'aihue was batting .195 with a .295 OBP. Moustakas is off to a decent start in Triple-A, hitting .267 with seven homers in 34 games, but third base hasn't been such a troubled spot in Kansas City where Wilson Betemit is batting .318 with a .382 OBP, though he doesn't have typical corner-infield power with just one home run. If the Royals need another pitcher beyond Duffy, lefty Mike Montgomery should be next in line.

Matt Dominguez, Marlins 3B

Dominguez's defense impressed in spring training, but his bat lagged a little behind, so he was relegated to Triple-A. He suffered a fractured left elbow just before the season started, putting his major league debut on hold while he rehabs, but there's little doubt the Marlins, who seem built to compete for the playoffs this year, could use him. The two men who have played the most third base for Florida in 2011, Greg Dobbs and Wes Helms, are both below-average fielders, though Dobbs is off to a great start at the plate (.337 average in 83 at bats).

Dominguez -- who was Moustakas' teammate at Chatsworth (Calif.) High (Moustakas played shortstop then) -- has begun his rehab assignment, batting .200 in his first 25 at bats in High-A and Double-A ball. He'll soon move to Triple A where he'll play while awaiting his crack at the majors.

Brandon Belt, Giants 1B

Belt made San Francisco's Opening Day roster after an impressive spring training (and an injury to corner outfielder Cody Ross), but he batted only .192 in 60 at-bats and was returned to Triple-A when Ross was activated from the DL. Further complicating Belt's major league stay was that he played first and Aubrey Huff attempted to play rightfield, where he was a defensive liability. Since Belt returned to the minors -- where he's batting .384 with a .525 OBP -- he has primarily played the outfield, however, meaning upon his return to the majors Huff can stay at first while Belt will join Ross in a corner-outfield rotation along with either Pat Burrell or Nate Schierholtz, depending on whom the team is able to trade and make room for Belt.

Julio Teheran, Braves RHP

In making one major league start on May 7 Teheran became the first player born in 1991 to reach the big leagues, and he'll be back in Atlanta this summer. That start wasn't spectacular -- he took the loss while allowing three runs in 4 2/3 innings to the Phillies -- but the Braves were pleased with the outing for the 20-year-old from Colombia, who had a 2.59 ERA, 1.04 WHIP and 10.0 K/9 while throwing 142 2/3 innings in Class-A, High Class-A and Double-A last year, earning him the No. 5 spot on Baseball America's preseason Top 100 list.

His return to the majors is a question of when, not if. The Braves are the rare team with starting pitching depth, boasting Derek Lowe, Tim Hudson, Tommy Hanson, Jair Jurrjens, Brandon Beachy, Mike Minor and Teheran. Beachy is presently on the DL, and the Braves could move a veteran like Lowe in search of more offense, which could open a rotation spot for Teheran. If not, he could contribute out of the bullpen late in the year -- and not just in long relief. After the Braves won the wild card last year, they didn't shy away from using late-season call-up Craig Kimbrel in tough spots in the Division Series against the Giants.

Brandon Guyer and Desmond Jennings, Rays OFs

Guyer already received a major league spot start and homered in his first at bat but was promptly returned to Triple-A Durham, where he and Jennings form two-thirds of what is probably the best outfield at that level. Jennings, who received a September call-up last year, is the bigger all-around prospect -- and the speedster is hitting .291 with a .404 OBP, five homers and eight steals -- while Guyer has more offensive pop, as he's batting .333 with six home runs and a .556 slugging percentage.

At the moment the two are biding their time while the Rays hold onto first in the AL East. Manny Ramirez's abrupt retirement opened a spot in the outfield after Johnny Damon moved to DH, but Sam Fuld more than capably filled it for the first month, though he is slumping now. While B.J. Upton and the streaking Matt Joyce aren't going anywhere, Guyer and/or Jennings could be given a chance to split time with Fuld or play a utility outfield role.

Brett Lawrie, Blue Jays 3B

The Blue Jays traded starter Shaun Marcum to the Brewers for Brett Lawrie, a 2008 first-round pick who had been playing second base and who was promptly moved to third base in the Toronto system. He's scorching the ball in his first season at Triple-A, with a .325/.381/.578 batting line, eight homers and 14 doubles in 166 at bats. And Lawrie could have an opportunity in Toronto, as he's barely being blocked on the parent club. Third base is currently manned by Edwin Encarnacion, who is suffering from a curious power outage -- zero home runs so far despite hitting 21 a year ago -- and from poor defense. His seven errors are tied for the most among major league third baseman.

Lonnie Chisenhall, Indians 3B

The Indians' second-rated prospect, starter Alex White, has already been promoted and cracked the starting rotation, leaving Chisenhall, a first-round pick in 2008, an obvious choice to be next in line. Baseball America projects him to be the organization's best average hitter, though so far he's only batted .273 in the minors. He has shown an improved ability to get on base this year, his first at Triple-A, posting a .373 OBP and 14 walks to with a .279 average, 10 doubles and three homers in 35 games. Incumbent Cleveland third baseman Jack Hannahan has just four singles in his last 29 at bats (.138), so Chisenhall could be called upon to add more offense.

The Indians' hot start -- at 25-13, they have the best record in the majors -- will encourage the front office into being more aggressive in chasing a playoff berth this year, which bodes well for Chisenhall and Jason Kipnis, Cleveland's top second-base prospect, who could also warrant a promotion before the year is done.

Anthony Rizzo, Pardes 1B

One of the premium prospects received from the Red Sox in the trade for Adrian Gonzalez, Rizzo has devoured Triple-A pitching so far this year. He's cooled off some in the past few weeks only because it was impossible to sustain a pace in which he began the year batting .452 with six home runs and 12 extra-base hits in 15 games. He's still crushing the ball to the tune of a .376/.448/.723 line with 12 home runs and 50 RBIs. His 1.171 OPS ranks second among all Triple-A players.

The Padres undoubtedly have a need for his bat. While Brad Hawpe has picked up his offense a little recently, the platoon of him and Jorge Cantu has left San Diego at a deficit. The Padres first basemen have an OPS of .600, which ranks 28th in the majors. Of course, though Rizzo has been the healthier, more impressive prospect, the club could instead promote Kyle Blanks for service-time reasons, as he has already played 87 big-league games over the past two seasons.

Jesus Montero, Yankees C/DH

The recent spat between the Yankees and Jorge Posada would be a poor auspices for Montero to make his major league debut -- potentially, teammates and/or fans could resent the rookie taking the veteran's job -- but Montero is probably a better-hitting version of 2011 Posada in that he is a catcher by trade who is best suited to be a DH (at least for now). The 21-year-old Montero is batting .336 with two homers in 30 games at Triple-A, a year after batting .289 with 21 home runs at that level last year. If Posada, who's hitting .165, continues to slump, Montero could get the call and be used as the backup catcher and DH against lefthanded starting pitchers.

Jacob Turner, Tigers RHP

The 6'5" Turner, the Tigers' No. 1 pick in 2009 who will turn 20 on Saturday, is off to a nice start at Double-A Erie, making seven starts for 45 1/3 innings and a 2.58 ERA and 1.06 WHIP. Given his age, he won't be rushed and probably won't see the majors this year -- unless Detroit decides the back of its starting staff could use a late-season boost.

In Justin Verlander and Max Scherzer the Tigers have one of the game's best 1-2 punches among starters. The back-end of the rotation, however, needs help. Brad Penny and Rick Porcello have been good, though a little inconsistent, but No. 5 starter Phil Coke, a former situational lefty reliever, is 1-5 with a 4.54 ERA and 1.37 WHIP. Those numbers aren't horrible for a fifth starter, but the Tigers have a real shot at winning the AL Central this year and might need to pull out all the stops, which could mean a promotion for Turner.