(ST. JOSEPH, Mo., AP) — Kansas City Chiefs safety Sanders Commings fractured his left collarbone in his first practice of training camp when he landed on it while trying to defend a pass.

The fifth-round draft pick jumped to defend tight end Tony Moeaki and landed hard on one of the practice fields at Missouri Western State University on Tuesday. Commings immediately walked off the field and was taken for X-rays that revealed the break.

Commings wasn’t wearing shoulder pads because players are barred from wearing them for the first three practices under terms of the most recent collective bargaining agreement.

The Chiefs hadn’t yet scheduled surgery Tuesday night, and a team spokesman said it wasn’t known how long Commings will be out. He was expected to provide depth in a secondary that underwent a massive overhaul this past offseason.