Clayton Kershaw will not start on Sunday against the San Diego Padres in the first game of the regular season in the United States.

An MRI showed inflammation in a muscle in Kershaw's back.

"It's nothing that I'm too worried about. It's really frustrating more than anything. The timing of it," Kershaw said.

"It's just one start that has to be pushed back. It's definitely something that if I had to pitch tomorrow, I could probably do it. It just wouldn't feel great."