By Bruce Levine-

MESA, Ariz. (CBS) — Due to the rehabbing status of Jake Arrieta, Carlos Villanueva will most likely begin the season as the Cubs 5th starter. The versatile 30 year old swing man was in that role last season, replacing the injured Matt Garza the first six weeks of 2013 in the rotation.

Villanueva started the season with eight rotation appearances going 1-3 with a 3.93 ERA before returning to the pen where he had an incredible season with a 6-1 record and a 3.03 ERA.

“He was big for us last year,” said pitching coach Chris Bosio. “For me he is one of the most valuable swing men in all of baseball. He has done both and had an incredible start to the season last year with an ERA in the high ones. Yeah, we are getting him ready just for that reason, in case he could be the 5th starter. That is why we come to camp with 12 potential starters. In the same breath if he is in the bullpen he is ready to give us a long reliever.”

Arrieta had a simulated start in Mesa on Sunday. Bosio said he would stay on an every five day pitching routine with a side session mixed in much like the regular season.

“Today was really good for him,” Bosio said. “We tried to simulate everything he would do on game day and he was right on his numbers.”

LHP Chris Rusin, RHP James McDonald and Villanueva are the choices for the 5th spot, that will be available on the 5th or 6th of April.

Watch & Listen LIVE