Manager Pat Murphy confirmed Koenig will attempt to rehab the injury and avoid surgery, with an expected return timeframe of two to four weeks. Koenig, who has been an 'unsung hero' for the Brewers the past two seasons with a 2.67 ERA over 127 games, had been experiencing decreased velocity in spring training, with his sinker averaging 93.5 mph in his last outing.
Lefty Shane Drohan was called up from Class AAA to replace Koenig and could make his MLB debut during the series at Fenway Park.