Cook talked Tuesday with manager Clint Hurdle and agreed to be scratched from his last scheduled start of the season, Friday night at Arizona. Right-hander Jason Hirsh, who hasn't started this season and didn't appear in the Majors until September because of a shoulder strain, will replace Cook.
That means Cook ends the year 16-9 with a 3.96 ERA in 32 starts. He made his first All-Star Game appearance this season and went three innings for the National League at Yankee Stadium. But during the second half, Cook had a start pushed back because of back tightness and has looked fatigued at times during the second half.
Cook finished one win shy of the club record for wins in a season, shared by Kevin Ritz (1996), Pedro Astacio (1999) and Jeff Francis (2007).
Originally, Cook said he would lobby to be allowed to start, but assessed his fatigue and discussed his situation with teammates, agent Joe Bick and pitching coach Bob Apodaca.
"'Dac' had talked to me even before my last start, told me to think it over, see if I really wanted to make the final start," said Cook, in the first year of a deal that will pay him $34.5 million through 2011 with a mutual option for 2012. "When I stepped back and got some space in between and evaluated where we were at, and what that start would mean, the only thing positive that could really come out of it was getting the 17th win."
Cook finished the year with two quality starts (six or more innings, three or fewer earned runs). He went eight scoreless innings in a duel with Greg Maddux on Sept. 14, a game the Rockies won in 10 innings, 1-0. Cook also held the D-backs to three runs (two earned) in 6 1/3 innings Saturday night.
After the game with the D-backs, an eventual 5-3 Rockies loss, Cook said he felt he owed it to the D-backs and Dodgers, who are trying to put away the D-backs in the NL West, to make the start because of the credibility of the division race.
"He just feels beat up," Hurdle said. "He's been red-lining. His last few starts have been very challenging for him. He said he wanted to give it every last minute he could to make a good decision, a representative decision."
Thomas Harding is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.