The Brewers did not make a formal announcement about Johnson's hire, but a source confirmed to MLB.com that he was leaving the Cubs for the Brewers. David Kaplan of CSN Chicago and ESPN 1000 in Chicago was first to report Johnson's move.
"People I've talked to who know him say this guy has an unbelievable mind; he's very creative, he's innovative," said Cubs pitching coach (and former Brewers pitcher) Chris Bosio after Chicago hired Johnson.
Johnson replaces Rick Kranitz, who was among five coaches dismissed from Milwaukee's staff at the end of manager Craig Counsell's first season. Kranitz was hired by the Phillies as assistant pitching coach this week.
Counsell had kept the staff intact after taking over as manager in early May, but he opted after the season to replace all but hitting coach Darnell Coles and third-base coach Ed Sedar.
One of Johnson's strengths, according to Cubs pitchers interviewed by MLB.com for a 2013 feature story, is maximizing players' mental strengths.
"Not that you're going to throw them on the couch and act like a psychologist or anything," Johnson said, "but it's really just trying to read them the best that you can and trying to understand where they're at based on the questions you're asking. And [it helps as far as] just trying to get to know them as well as you possibly can so the changes you are trying to make, you make them at the right time and you do the right thing by them."
He added: "It's not just how you move your arm or your leg or what you do in the weight room and all that. It's about the person inside, it's about trying to maximize as much as you possibly can out of someone, and the only way you do that is get to know them."
The Brewers ranked 24th of 30 Major League teams with a 4.28 ERA, and 28th with a 4.79 ERA from the starting pitchers, a figure inflated by career-worst years for veterans Kyle Lohse and Matt Garza. Johnson will inherit a staff stocked with young pitchers after Garza, a list that includes Wily Peralta, Jimmy Nelson, Taylor Jungmann and Zach Davies.
Adam McCalvy is a reporter for MLB.com. 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.