"If we have somebody who is a good fit on the field and off the field, we can look to extend them. We've signed some extensions with our own guys and we'll continue to do that as well."
Baker, 31, is the type of pitcher the Cubs want in the rotation, boasting a career WHIP of 1.264. Epstein called the right-hander a "pitch maker."
"I think there's a chance Scott likes it here in Chicago and we like what we have in him and we can talk about making this a longer term relationship at a point down the road," Epstein said.
Baker said he isn't thinking about what could happen at the Trade Deadline or beyond.
"That's a far stretch in my opinion," he said. "One, I'm coming off an injury. I know it's an injury with a high success rate. We'll just have to see how things work out. First and foremost, I want to be healthy and productive and I feel that would be getting a little ahead of myself trying to think about [being dealt to a] contender and all that."
The Cubs have two healthy pitchers set for the 2013 rotation in Jeff Samardzija and Travis Wood. This week, they should get an update on Matt Garza, sidelined since late July. Garza, who made 18 starts before he was shut down with a stress reaction in his right elbow, was to have a scan done on his arm.
The Cubs are in the market for at least one more starter.
"We're pursuing pitchers across the spectrum," Epstein said. "[We're looking at] some guys who might be classified as buy low, there might even be buy-high guys, some multi-year deals, some trades. We're looking for pitchers who can step in and improve our rotation. If there are sound investments out there, whether they're big or small, we'll pursue them and try to sign them."
The Baker contract, which will pay the right-hander $5.5 million and includes another $1.5 million in possible performance bonuses, was finalized at the General Managers Meetings last week. Epstein said it was time well spent as he and general manager Jed Hoyer met with agents and talked to teams about possible trades.
"Even if you pursue leads and you realize it's not going to go anywhere, you put them at the bottom of the priority list, and that's helpful because it allows you to spend more time on things that might have a chance of working out," Epstein said.