Jake Arrieta says he'll be ready for Opening Day on April 4 despite leaving Thursday's spring start against the San Francisco Giants in the first inning with a blister on his thumb.

"[We] noticed in the bullpen I was having a hard time with it," Arrieta said. "No point in staying out there and having the same thing happen over and over again to each hitter."

Arrieta allowed five runs in the first inning of the Chicago Cubs' eventual victory.

The right-hander blamed the dry Arizona climate for the blister on his thumb Thursday and for one last week as well. He said he used super glue to cover it, but the glue caused the ball to slip out of his hand.

"It was tender, and the skin was starting to come apart again," Arrieta said. "It's from the dryness out here.

"Everything was slipping off my thumb. Couldn't really finish or get the good rotation on my breaking stuff. It's really not that bad."