When Rodriguez reported to camp in 2007, he had reduced his body fat from 16% the year before to 9%. He made light of this fact during a Late Show with David Letterman sketch that was filmed during Spring training, which featured him shirtless being rubbed down with suntan lotion. He revealed to the press that he and Jeter were no longer close friends. Rodriguez also reduced his high leg kick at the plate, increasing his bat speed, making him less-apt to strike out and a more dangerous hitter.
In 2007, Rodriguez became the first player in major league history to have at least 35 home runs, 100 runs, and 100 RBIs in 10 consecutive seasons, surpassing Jimmie Foxx (9 consecutive seasons). He led the AL in home runs (54), RBIs (156), slugging percentage (.645), OPS (1.067), total bases (376), and times on base (299), and was 2nd in hit by pitch (21), extra base hits (85), and at bats per home run (10.8), 4th in on-base percentage (.422) and sacrifice flies (9), 7th in walks (95) and plate appearances (708), 8th in intentional walks (11), and 9th in games (158). He led MLB in home runs and won his third Babe Ruth Home Run Award.
The 2007 season marked the last year of Rodriguez's 10-year, $252 million contract before he opted out and became a free agent again. Rodriguez had repeatedly stated during the 2007 season that he would like to remain a Yankee for the rest of his career. On October 28, 2007, Rodriguez's agent, Scott Boras, announced that he would not renew his contract with the Yankees citing that he "was unsure of the future composition" of the team. He received a slew of criticism from fans and writers alike not only for opting out, but also for not meeting with Yankee management before he did. He was further criticized for the timing of his announcement, during the eighth inning of Game Four of the World Series, as the Boston Red Sox were wrapping up their victory over the Colorado Rockies; even MLB's chief operating officer, Bob DuPuy, called it an attempt by Boras to "try to put his selfish interests and that of one individual player above the overall good of the game."
Teammate Mariano Rivera convinced Rodriguez to contact the New York Yankees ownership. He contacted them directly, bypassing Boras (Boras also apologized for the timing of the announcement). Subsequently, Rodriguez issued a statement on his website, saying that he wished to stay with the Yankees. On November 15, 2007, the New York Yankees and Rodriguez agreed on the "basic framework" of a 10-year, $275 million contract that would have him playing until he is 42. The contract, finalized December 13, included various multimillion-dollar incentives for breaking career home run milestones.
Rodriguez hit his 549th home run in a September 3, 2008, game against the Tampa Bay Rays. The opposing manager objected that the ball was foul, and for the first time in MLB history, instant replay (a process officially introduced a few days earlier) was used to review the play and uphold the umpires' ruling. He was one of only four batters in the AL to have at least 18 home runs and 18 stolen bases in both 2007 and 2008, along with Torii Hunter, Ian Kinsler, and Grady Sizemore. Rodriguez hit a home run every 14.6 at-bats in 2008, the second best ratio on the team behind Jason Giambi. Rodriguez played 138 games during the 2008 season with a .302 average, 35 home runs, 103 RBI, and an AL best .573 slugging percentage.
In July 2007, former outfielder and steroid-user Jose Canseco said that he was planning to publish another book about Major League Baseball, to follow his 2005 bestseller Juiced: Wild Times, Rampant 'Roids, Smash Hits & How Baseball Got Big. Canseco said his new book would have "other stuff" on Rodriguez, and called him a hypocrite. At the time, Rodriguez denied accusations of steroid use. In a 2007 interview with Katie Couric, Rodriguez flatly denied ever having used performance-enhancing drugs.