It was a good feeling for Middlebrooks, who fractured his right wrist last Aug. 10.
"It felt good," Middlebrooks said. "It felt good to hit a ball hard. My first at-bat this spring, I hit one hard and then since then, I haven't really had good contact over the past couple of games, so it felt good just to see a curveball early, stay back and hit it hard."
This was a far better feeling for Middlebrooks than six days earlier, when he felt discomfort in his right wrist on a check swing and had to leave the game. Fortunately, Middlebrooks wasn't actually injured in that case. He thinks it was just some scar tissue breaking up.
"Yeah, I've got to get over mentally thinking about it and worrying about it," said Middlebrooks. "I'm going to be sore. I'm going to have tightness. That's just getting back into it. That's what happens after an injury like that. It's more of a mental thing and just being able to let it go."
Middlebrooks could be a huge factor in Boston's lineup this season if he can build on what he did his rookie year.
"Over the last couple of days he's been a little more aggressive at the plate, particularly with some pitches on the inner half," said manager John Farrell. "As every guy gets additional at-bats, their timing gets a little better, they get more comfortable in the box, and that's what's taking place with Will."
Ian Browne is a reporter for MLB.com. Read his blog, Brownie Points, and follow him on Twitter @IanMBrowne. This story was not subject to the approval of Major League Baseball or its clubs.