An MRI on Duffy's injured elbow Sunday revealed no UCL damage, Jeffrey Flanagan of MLB.com reports. He was officially diagnosed with a low-grade pronator strain.

EDGE Analysis

Sunday's MRI revealed no further damage to Duffy's injured left elbow. Manager Ned Yost confirmed that the team is hopeful that their ace will only be forced to miss one start, though he noted that Duffy could be sidelined for up to three weeks in what would be a worst-case scenario.