It's quite possibly the last start in a Rockies uniform for Cook, 32, who has struggled (3-9, 5.74 ERA) in 16 starts after missing the first two months of the season with a broken ring finger on his right hand. The Rockies dropped him from the starting rotation last week. Cook has an option for 2012 worth $11 million, which means the Rockies are almost certain to pay a $500,000 buyout.
Wednesday's start is more of a thank you for his long run with the organization, which drafted him in the second round in 1997. Since debuting in the Majors in 2002, Cook has gone 72-67 with a 4.50 ERA in 236 games, including 205 starts. He is by far the most successful starter the Rockies have ever selected in the First-Year Player Draft. Jason Jennings is next with 58 wins.
"He's made a lot of significant contributions to the success of this ballclub over the course of the last few years, dating back to 2007," Tracy said. "He well deserves that opportunity."
Cook overcame an oblique muscle injury at the end of 2007 and returned for Game 4 of the World Series, which was the Rockies' best-pitched game in their four-game sweep at the hands of the Red Sox. Cook also threw three scoreless relief innings in the '08 All-Star Game, and beat the Phillies in Game 2 of the '09 National League Division Series.
"He's done it extremely well, he's done it with a lot of class, he's done it with a lot of competitive nature about him," Tracy said. "As I remember, I was fishing on Lake Erie when I watched it, the effort that he gave in the All-Star Game back in 2008.
"I believe Carlos Marmol, they wanted him to go an extra inning and he said he couldn't do it. Then they ended up playing  innings, and there was Aaron Cook giving them three tremendous innings."
Tracy said he hopes to find some relief innings before Wednesday for Cook, who has not pitched in a game since Sept. 4.