By Bruce Levine–

SAN DIEGO (CBS) — Moving forward!

READ MORE: Chicago Weather: Rain Followed By Colder Temps

That’s the battle cry for the Cubs, despite the unknown in the Jon Lester sweepstakes. After signing Jason Hammel to a two-year deal, the Cubs, looking for an upgrade in catching and left-handed hitting, traded for Arizona catcher Miguel Montero on Tuesday.

The price of two decent minor league pitching prospects is really not their major concern at this juncture. The Cubs front office believes the only way to win championships is continuing to upgrade at every position on the field. Many would argue that incumbent catcher Welington Castillo had improved his skills every year over the past three seasons, and that opinion may indeed be valid. It’s also worth considering that Castillo had a long way to travel when Theo Epstein and Jed Hoyer began their Cubs careers three years ago.

The complaint from front office types as well as certain pitchers from time to time insisted Castillo wasn’t adept at framing pitches or calling for the best pitch in certain crucial situations. All the above critics loved Castillo’s work ethic and improved skills. Despite those positive comments, not many would predict a better outcome in his deficient areas.

Montero is regarded as a strong defensive catcher who’s a quality pitch framer.

READ MORE: My Block, My Hood, My City Volunteers Robbed While Holiday Decorating In Bronzeville

“Players that do everything well tend to become household names,” Epstein said. “A few guys in each generation do that well, and they end up catching for 20 years. I think our move today is a recognition of the real importance of catching to a good team, to a team that wants to be good and contend. It’s hard to put yourself in a position of being vulnerable to one injury and not have a good solution.”

Montero hit .243 with 13 homers and 72 RBIs and a .699 OPS in 136 games with Arizona last season. He’s a career .264 hitter with a .763 OPS.

Epstein didn’t rule out trading Castillo but said that isn’t what the team is trying to do. A platoon of Montero and Castillo is expected. Montero would probably start 10 out of every 12 games or so just because of his left-handed bat.

“These two guys complement each other extremely well,” Epstein said. “The whole will be greater than some of our parts. I look forward to (seeing) how they will work together.”

The Cubs assume payment of the entire $40 million salary due to Montero over the next three seasons.

MORE NEWS: Teen, 15, Shot In The Loop

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