But the right-hander stayed in the game, and he went 5 2/3 innings in a 6-1 win over the Yankees. On Wednesday, he arrived late at the clubhouse because he could only pack for the team's road trip with his left hand. X-rays taken Tuesday were negative, and Hammel pronounced he was good to go for his next start Sunday against the Padres.
"It's just swollen," he said. "I would assume a couple days of soreness. I think it'll be all right."
Cubs manager Rick Renteria said it was "scary" to watch Hammel get struck with the liner, but he was encouraged after talking to the pitcher Wednesday.
"He feels better than he thought he would, and the swelling isn't as significant as he thought it would be," Renteria said. "Fortunately for us, he's a gamer. He stayed in there."
Hammel didn't get much sleep Tuesday because he would flex his hand every now and then and also treated it with an ice pack.
"In my game plan, I'm going to make that start [Sunday]," he said. "If I can go after getting hit, I can start."
Carrie Muskat is a reporter for MLB.com. She writes a blog, Muskat Ramblings, and you can follow her on Twitter @CarrieMuskat. This story was not subject to the approval of Major League Baseball or its clubs.