He played in Major League Baseball (MLB) for the New York Mets, Florida Marlins, Kansas City Royals, and Arizona Diamondbacks.

Mike Jacobs graduated from Hilltop High School in Chula Vista and spent one season at Grossmont College in El Cajon, California before being selected by the New York Mets in the 38th round of the 1999 Major League Baseball Draft.

In May 2004, while playing for the Triple-A Norfolk Tides, Jacobs suffered an arm injury and underwent surgery for a torn labrum, which ended his season prematurely.

Because of his injury and mediocre defensive skills behind the plate, when Jacobs returned to Binghamton in 2005, he spent much of the season learning to play first base.

[4] Jacobs rather instantly assumed the position of everyday first baseman and continued to hit, tallying four home runs through three games, during the Mets' 4-game drubbing of the Arizona Diamondbacks.

During this stretch the Mets were able to pull within a half-game of the National League Wild Card lead, but faded quickly, dropping two straight games at home to the Philadelphia Phillies and promptly falling out of the race.

Jacobs continued to play well, increasing his stock as a trade chip by slugging a monstrous .710 in his five weeks as a major leaguer.

However, on November 23, 2005, the Mets traded him and a minor league pitcher, Yusmeiro Petit, to the Florida Marlins in exchange for Carlos Delgado and $7 million.

In 2008 Jacobs saw increased playing time and had a break out season in power with 32 home runs and 93 RBI but his batting average slipped to .247.

[5] While initially thought to split time at first base with Billy Butler, he was mostly the team's DH due to inconsistent play on the field.

[8] On August 18, 2011, while playing for the AAA Colorado Springs Sky Sox, Jacobs was suspended for 50 games after testing positive for Human Growth Hormone.

This was apparently not known to the Marlins when, on May 28, 2006, as part of the team's Jewish Heritage Day promotion, they gave Jacobs T-shirts to young fans who attended the game.