By Bruce Levine–

(CBS) With the non-tender period for players who were arbitration eligible come and gone, the Chicago Cubs may have in their sights a on a front-of-the-rotation pitcher for now and the future.

On Friday night, the San Diego Padres didn’t offer 29-year-old right-hander Tyson Ross a contract. Ross becomes a free agent, able to sign with any of the 30 clubs, including the Padres. He underwent surgery to remove pressure in his right arm in October, and his rehab will take from four to six months. The surgery was a success, sources said.

Ross had thoracic outlet syndrome, a serious injury that cuts off blood flow from the shoulder to the rest of the arm. It limited him to one start in 2016. Ross had successful surgery, but the rehab time and effects of the injury must be carefully weighed for interested suitors. Ross has had a star-crossed career that includes a 32-53 record, a 3.64 ERA and 1.32 WHIP. Pitching on poor offensive clubs can fog up any pitching line, and such is the case for Ross.

The Cubs — who had the best and most proficient starting rotation in baseball in their 2016 championship season — must replace Jason Hammel in 2017 after letting him walk to free agency. Ross could be that pitcher by late April or early May. He had his best years in 2014 and 2015, when he posted ERA of 2.81 and 3.26, respectively. Ross also averaged more than 200 strikeouts across those two seasons.

Both Cubs president of baseball operations Theo Epstein and general manager Jed Hoyer have said they will be looking at all types of pitchers to add to the team. They insisted rehabbing pitchers will be on their radar screen as well. It’s worth noting the Cubs have tried to obtain Ross numerous times over the past two seasons.

“The Padres were close to trading Ross to the Cubs for Starlin Castro,” said a major league source who once worked for one of the clubs. “San Diego execs were mixed on asking for Castro or Javier Baez. The deal went down to the wire in late July of 2015 but never got to the point of exchanging medicals.”

The Cubs will likely be creative with their offer if they decide to gamble on Ross. A two-year deal with plenty of incentives and option years for both sides could make sense. The beauty of a deal like this can be two-fold for Chicago.

First and foremost, the Cubs don’t have to give up any players to obtain a pitcher they long have desired. Such players could then still be available for other trades, if need be. Adding another starter could also push lefty Mike Mongomery back into a bullpen or a sixth starter role.

Manager Joe Maddon has insisted a sixth starter in baseball rotations may indeed be the wave of the future. Maddon employed Adam Warren and Montgomery in those roles during 2016.

Ross is represented by the Wasserman Media Group headed by veteran agents Joel Wolfe and Adam Katz.

With a top-rated pitching coach in Chris Bosio, the Cubs have a man who can help turn rehabbing and reclamation projects around. He has worked his magic before with Jake Arrieta, Kyle Hendricks, Pedro Strop, Hector Rondon and Montgomery, to mention just a few.

Is there a match with Ross and the Cubs? Bet on it.

Bruce Levine covers the Cubs and White Sox for 670 The Score and CBSChicago.com. Follow him on Twitter @MLBBruceLevine.