NBC Sports has learned that free agent left-hander Mark Mulder has opted to retire. Mulder appeared set to join the Brewers after working out with now pitching coach Rick Peterson. The 32-year old left-hander hasn't pitched a full season since 2005, when he went 16-8 with a 3.64 ERA in 32 starts.
Mulder did string together five consecutive seasons of 16 wins or more, and owns a career 103-60 record with a career 4.18 ERA in nine seasons with the A's and Cardinals.
The report came from Milwaukee, which was then confirmed by Brewers pitching coach Rick Peterson to MLB.com.