The MLB's Five Biggest Call-Ups of 2010

Call-ups can make or break your team, and that's why they are so important.

Injuries in the MLB are not a given, so any player at any time could be called up to replace a roster spot.

Here is a look at the five biggest call-ups of the 2010 baseball season.

Stephen Strasburg

Stephen Strasburg was an early June call-up and immediately made his presence felt.

In only his first start in the MLB, Strasburg struck out 14.

Now, Strasburg is injured, but here is a look at his stats through three months in the bigs:

• W-L 5-3
• ERA 2.91
• K 92
• Walks 17

Madison Bumgarner

Madison Bumgarner was called up by the Giants to add to an ailing rotation.

Bumgarner, who didn't make the cut in spring training, is a talented lefty that will add even more power pitching to this already extremely talented staff.

• W-L 5-4
• ERA 3.95
• K 52
• Walks 19

Jason Heyward

Jason Heyward was an immediate impact in Atlanta, with a home run in his first Major League at-bat.

Heyward continues to live up to the hype he had while in the Minors.

• Avg .278
• HR 16
• RBI 62
• Runs 72
• SB 9

Pedro Alvarez

Pedro Alvarez was called up by the Pirates, and started in a slump.

He later began to hit for power and contact and began producing runs. Alvarez was one of the top-ranked prospects by Baseball America.

• Avg .234
• HR 10
• RBI 36
• Runs 24

Buster Posey

Buster Posey has been called the future of the San Francisco Giants.

He brings so much energy and youth to the table, and along with his bat, his career will go far.

Posey was an immediate impact call up by the Giants, and Posey took over for the traded Bengie Molina right away.

• Avg .328
• HR 10
• RBI 50
• Runs 40

Honorable Mentions

Aroldis Chapman - Look for Chapman, who was clocked in at 103 MPH, to be an immediate impact for the Reds and live up to his hype

Jeremy Hellickson - Called up by the Rays with two pitchers placed on the DL, Hellickson has been masterful going 3-0 with a 2.05 ERA

Carlos Santana - Santana added a big extra bat to the Indians, showing off his power early

Ike Davis - Davis was a major call-up for the Mets that has helped them tremendously, and is now a fan favorite

Travis Wood - Wood was a call-up by the Reds due to injury, and is only his second major league start, he flirted with a no-no

Barry Enright - Barry Enright has become an amazing addition to the Arizona Diamondbacks, going 5-2 with a 2.44 ERA

Chris Johnson - Chris Johnson was an addition to the Astros to fill in at third base. Since his call up he is batting .329 with 36 RBI

Stats courtesy of Yahoo!