New York, NY (My Sportsbook) - A night after informing the Yankees that he would opt out of his contract, third baseman Alex Rodriguez officially filed for free agency.

Rodriguez, who will lose about $72 million of guaranteed money by escaping an original 10-year, $252 million deal he signed with Texas prior to the 2001 season, was one of 57 players to file for free agency on Monday. It was the first day of filing following Boston's sweep of Colorado in the World Series.

Rodriguez leaves a Yankee legacy that includes an MVP award from 2005 and a likely MVP for this stellar season, in which he blasted 54 homers, drove in 156 runs and batted .314. However, he struggled mightily in the postseason, particularly since the Yankee collapse against the Boston Red Sox during the 2004 ALCS. In the last three playoff years, all first-round Yankee losses, Rodriguez was just 7-for-44.

Also filing was home run king Barry Bonds of the San Francisco Giants. Bonds returned for his 15th season with the Giants after signing a one-year, $15.8 million contract prior to the season. Then, on August 7, he took Washington left-hander Mike Bacsik deep to pass Hank Aaron as baseball's all-time home run leader. Bonds stands at 762 career homers, and has expressed a desire to play a 23rd season in the majors.

Center fielder Torii Hunter, who also filed Monday, will be a popular commodity this offseason. The six-time Gold Glove winner had career highs of 172 hits, 45 doubles, 107 RBI and a .287 batting average to go along with 28 homers in 2007 for Minnesota.

Two other prominent Yankees also filed for free agency on Monday in closer Mariano Rivera and catcher Jorge Posada. The owner of a major league record 34 saves in the postseason, Rivera has played his entire career with the Yankees, compiling 443 saves in 13 years. The 37-year-old righty had 30 saves to go along with a 3-4 record and 3.15 ERA this season. Posada, another career Yankee, hit a career-best .338 with 20 homers and 90 RBI this year.

Detroit closer Todd Jones and Philadelphia Phillies outfielder Aaron Rowand became free agents as did outfielder Milton Bradley of the San Diego Padres and third baseman Pedro Feliz of the Giants.

The Mets and Astros led the way with six players filing from each team. Outfielder Shawn Green and catcher Paul Lo Duca filed for New York, while catcher Brad Ausmus and infielder Mark Loretta did the same for Houston.