MLB 2011: Dustin Ackley and the Top 5 Midsummer Call-Ups

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For every Jason Heyward that begins his rookie year right from Opening Day, there is a Buster Posey who is called up in the summer to delay his major league service clock.

These two rookies played an equally significant role for his respective team in 2010, though they reached the majors at different times.

Midsummer call-ups can alter a pennant race and a team’s fortune for that season, and 2011 won’t be different.

There are several talented rookies that will start 2011 in the minors, whether it’s to delay their service clock or tweak something minor in their game.  However, come June, many of them will start to be called up.

Here are five players who will be called up this summer who will have the biggest impact.

5. Jordan Lyles, P, Astros

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Lyles was in the running for the Astros’ fifth starter spot to begin 2011, but that position has been given to veteran Nelson Figueroa.

Nevertheless, Lyles will see the majors in either June or July.

Houston will either need Lyles’ service due to a lack of productivity, or they will make a trade, freeing up a position in their rotation for their top prospect.

4. Matt Dominguez, 3B, Marlins

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Dominguez got off to a great start this spring, and was the frontrunner to win the third baseman job for the Marlins before his abysmal slump.

There is no doubt his glove is ready, and once he finds his stroke again in the minors, Dominguez will take over the hot corner for the Marlins.

3. Julio Teheran, P, Braves

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One of the top prospects in the game could be a deciding factor in the NL East and Wild Card races this season.

Teheran’s talent is too much to ignore, so even if one of Atlanta’s starters doesn’t go down with an injury or their fifth starter does produce, Teheran could find himself in a very big role out of the bullpen.

2. Mike Moustakas, 3B, Royals

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Arguably the Royals’ top prospect, Moustakas hit 36 homers in the minors in 2010.

He will start the season in the minors to delay his major league service clock, but don’t expect him there for too long.

Moustakas should be in the majors by July.

1. Dustin Ackley, 2B, Mariners

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Ackley has the talent and is ready to begin the season in the bigs, but the Mariners will send him down to the minors until June to delay his service clock.

Once Ackley arrives, he could produce much like Buster Posey did last season.  He won’t be able to lead the Mariners to playoffs like Posey did, but he will be a cornerstone in that franchise for years to come.