Now they are reunited in Milwaukee.
"It's huge to have that familiarity with a guy and be comfortable with him," Ramirez said. "He believes in what I can do. Last year, dealing with the injuries and stuff, I know he's seen me when I'm good, and he knows what I can be."
Ramirez had a 1.44 ERA in 50 appearances for the Rick Renteria-managed Cubs in 2014, but he was limited to 19 games by a shoulder injury in 2015, Joe Maddon's first season. Ramirez says he is healthy again, but he pitched only eight times before the Cubs designated him for assignment on May 21.
"I didn't really, necessarily talk to Maddon a whole lot about it," Ramirez said. "I just went about my business and was ready every day. Probably missing a lot of time last year, he found some guys he really trusted, and to their credit, they threw well. It could be a mixture of things. I always said that I was healthy and ready to go.
"It's going to be a little different [being on the other side of the rivalry]. The good thing is I know those guys really well, and I think I have a good idea of how to get them out. Hopefully I can help on the other side of it, too: Give our guys some tips and hints of how to get their guys out. Obviously we face them a lot during the year, and I think where this club is at now is where [the Cubs] were at a couple of years ago, in that rebuilding stage.
"The thing about a winning ballclub -- I've been on one that wasn't winning [in 2014], and then winning last year -- it's very minor. It's a few adjustments here and there, and then getting some confidence and running with it."
Adam McCalvy has covered the Brewers for MLB.com since 2001. Follow him on Twitter @AdamMcCalvy, like him on Facebook and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.