The injury occurred early in Friday night's loss to Detroit, when Middlebrooks -- shifted up toward the infield grass, in anticipation of a potential bunt -- fielded a hooking line drive from Ian Kinsler. The swelling continued throughout the game, to the point where it affected his grip on the bat. An MRI on Saturday revealed the fracture.
"I was in for bunt purposes. He's a guy, he'll drop one down if you're back, so I was playing up close and he hit a screamer at me, obviously," Middlebrooks said. "Had some top spin, kind of went with both hands for some reason to try to catch it, and it went under my glove.
"Thought it just bruised me, jammed me pretty good and then it just kept swelling and kept swelling throughout the game. By the eighth (inning), I couldn't even get batting gloves on."
Even as the pain persisted, Middlebrooks said he did not want to come out of the game.
"I hit with it twice, or attempted to hit with it twice. I was able to hit with it off the bat but throwing was pretty tough," he said. "I think I got three or four plays after it happened. I knew the grass was wet so I could skip it over to Napoli if I needed to. Just tried to make it through. I was like, 'I just jammed it, bruised it and it'll be better tomorrow, ice it up, whatever.' And then it just kept getting worse and getting worse."
Manager John Farrell said Middlebrooks will have his finger in a splint for approximately 5-to-7 days.
"Depending on how he responds to treatment, we'll first look to initiate any baseball activity. It's hard to say at this point how long he'll be down," Farrell said.