After the 2003 season, Pettitte left the Yankees, signing a 3-year, $31.5 million contract with the Houston Astros. He switched his uniform number to #21, in honor of Roger Clemens, who previously wore that number in Boston and Toronto. His 2004 season, in which he held batters to a .226 batting average, was shortened by elbow surgery. Pettitte returned to form in 2005 to help the Astros make their first trip to the World Series. His 2.39 ERA in 2005 was a career-best, and 2nd-best in the National League behind teammate Roger Clemens. He was also 2nd in the league walks/9 IP (1.66) and LOB percentage (79.7%; a career best), 3rd in sacrifice hits (15), 5th in wins (17), and 8th in W-L pct. (.654). He held lefties, who over his career have outhit righties when batting against him, to a .200 batting average, had a career-best 4.17 SO/BB ratio. After the 2006 season, Pettitte left the Astros, and signed a 1-year, $16 million contract with the New York Yankees with a player option for 2008 worth $16 million. On January 11, 2007, Pettitte was re-introduced as a Yankee at a Yankee Stadium press conference. Pettitte won his 200th career game on September 19, 2007. In 2007 he led the American League in starts (34), was 7th in batters faced (916), and was 9th in innings pitched (215.3), finishing the regular season with a 15–9 win-loss record. He also had the 5th-lowest HR/9 innings pitched ratio in the AL (0.67).
Andy Pettitte - Pitching
Pettitte won 20-games in a season twice, posting 21–8 records in 1996 and 2003. Pettitte was part of seven American League pennant-winning teams, one National League pennant-winning team and five World Series championship teams. He holds the record for most wins in postseason history with 19. He is the only MLB pitcher since 1930 to win at least 12 games in each of his first nine seasons. For his career, Pettitte had a 240–138 win-loss record with a 3.88 ERA and 2,251 strikeouts in 3,055 1⁄3 innings. He also never had a losing season in Major League Baseball. Pettitte and teammate Mariano Rivera have combined for a record 68 win-save combinations, the most in history. Pettitte, Rivera, Derek Jeter and Jorge Posada have been noted as the "Core Four" as they had been teammates for the five World Series won between 1996-2009. Pettitte was 19–10 with a 3.83 ERA and 173 strikeouts in the postseason (1995–2003, 2005, 2007, 2009–2010), with the most postseason wins in the history of Major League Baseball. He also holds the all-time record for most starts and innings pitched in the post-season (42 and 263, through 2010). He was the second starting pitcher in history to win three series-clinching games (ALDS, ALCS and World Series) in the same postseason (2009). Derek Lowe did the same in 2004, but with one of the wins in relief, and additionally, Pettitte won the game where the Yankees clinched the division. When Pettitte started Game 3 of the 2009 World Series, he passed Christy Mathewson and Waite Hoyt, with the second most World Series starts. Whitey Ford is in front with 22 starts. Pettitte has played in 8 different World Series (7 with the Yankees, and one with the Astros), and been on the winning end of 19 postseason series – both of which are tops among active players. During the period from 1995–2010, no major league pitcher accumulated more victories. His 148 wins from 2000 to 2009 were the most in the decade. Pettitte threw a four-seam fastball, a cutter, a curveball, a sinker, a changeup, a slider, and a 12-6 curveball. His out pitch was the cutter at 85–88 mph with good inside break on right-handed batters, resulting in a lot of ground ball outs and double plays. At the end of his career, his fastball was measured in the lower 90s and his curveball was about 74–76 mph.
On September 30, 2006 the Los Angeles Times reported that former relief pitcher Jason Grimsley, during a June 6, 2006 federal raid by federal agents investigating steroids in baseball, named Pettitte as a user of performance enhancing drugs. The Times reported that Pettitte was one of five names blacked out in an affidavit filed in federal court. Grimsley had told investigators that he got amphetamines, anabolic steroids, and human growth hormone (HGH) from someone (later named as Kirk Radomski) recommended to him by former Yankees trainer Brian McNamee, who is a personal strength coach for Clemens and Pettitte. However, on October 3, 2006, the Washington Post reported that San Francisco United States attorney Kevin Ryan said that the Los Angeles Times report contained "significant inaccuracies." Contrary to the initial LA Times report, neither the name of Clemens nor Pettitte appeared in the affidavit submitted by Grimsley. On December 13, 2007, Pettitte was one of several Yankees named in the Mitchell Report. Mitchell and his staff received the information on Pettitte from McNamee, who told them he injected Pettitte with HGH on 2–4 occasions in 2002 so that he would heal from an elbow injury quicker. On December 15, 2007, Pettitte verified McNamee's claim, admitting to using the HGH on two occasions in 2002, as it was meant to help heal an injury, and not to enhance his performance. Pettitte said he felt an obligation to return to the team as quickly as possible. He denied any further usage of HGH during his career; he also denied use of steroids or any other performance-enhancing drug. On February 13, 2008, in an affidavit made public as part of a hearing before the U.S. House of Representatives' Committee on Oversight and Governmental Reform, Pettitte admitted to additional injections of HGH twice in one day in 2004, using HGH obtained via prescription for his seriously ill father. Also in this affidavit Pettitte unequivocally recalled being told by former Yankees teammate Roger Clemens in 1999 or 2000 that Clemens had recently received injections of HGH. Clemens claimed during the noted hearing that Pettitte "misremembered" Clemens's 1999/2000 HGH remark, alleging that what Pettitte really heard was Clemens's reporting of his wife's use of HGH at that time, though earlier during this same hearing Clemens denied knowing of any use of HGH by his wife. McNamee corroborated Pettitte's recollection of events. On February 18, 2008, Pettitte reported to Yankees spring training and apologized to fans for his past drug use. In the press conference, he said the performance-enhancing-drug scandal has put a "strain" on his relationship with close friend and former teammate Roger Clemens.