After fourteen Major League seasons, infielder Bret Boone is calling it quits for good, according to The Associated Press. "I had no idea how hard it is when you get to be a certain age," Boone told ESPN.com. "My whole life, when the older guys would tell me, I would laugh at them -- like, 'That would never happen to me.' Now I know what 39-year-old middle infielders feel like playing every day. Wow -- it's very hard." Boone was a three-time All-Star and four-time Gold Glove winner. He initially retired back in 2006. "When I walked away the first time, I had a lot of issues going on, and I wasn't in a good place. I came back with a clear mind and a clear head, and I know where I was as a player at this stage of my life. I'm glad I made the decision," Boone said.