Koenig, who had been an 'unsung hero' for the Brewers with a 2.67 ERA over 127 games in his first two seasons, will attempt to rehab the injury and avoid surgery with a potential return in 2-4 weeks. His velocity decreased this spring, averaging 93.5 mph in his last outing.
Shane Drohan was called up to replace Koenig and may make his MLB debut at Fenway Park. The left-hander was traded from Boston to Milwaukee in the Caleb Durbin deal and downplayed any significance of potentially facing his former team.