Now that he's the manager of the Boston Red Sox, that number is already taken by center fielder Jacoby Ellsbury. Valentine thought about wearing No. 22, but current bench coach DeMarlo Hale has the number stitched on his back.
So, Valentine decided to wear No. 25 in honor of Tony Conigliaro.
Tony C, a Massachusetts native and legendary Red Sox right fielder, died at age 45 in 1990. With the Red Sox in 1967, he was hit in the face by a pitch on the left side of his face and suffered serious injuries. He was never the same after.
"I know 25 is really Tony C's number," said Valentine. "I might have been his last roommate, and I think I was. He was trying to make a little comeback when I was with the Padres and I had such admiration for him.
"We both got beaned and I never was able to talk to someone about that, when that ball slows down right there [a few inches from the face], right before the impact and it's a lousy conversation, but I was able to talk to him about it. It was a bonding sort of thing."
When Valentine realized no current Red Sox player was wearing No. 25, he called Mike Lowell, who also wore the number during his career with the Red Sox, to ask his blessing.
Valentine also admitted he wanted to call Tony C's brother, Billy, to ask the Conigliaro family permission to don the number.
"I know a lot of people want it to be retired in his honor, and I would gladly put it up on that wall rather on my back," Valentine said of No. 25. "I think it's a great number to wear."