Brian Callahan had a confusing explanation for not using a challenge Sunday

The Titans lost to the Broncos in Denver on Sunday afternoon, but they may have given themselves a better chance of winning the game if they had a firmer grasp of the rules governing what constitutes a catch.

Rookie wide receiver Elic Ayomanor went up to try for a pass from Cam Ward with the Titans trailing the Broncos 13-12 in the third quarter and was ruled to have come down out of bounds while making the grab. Replays showed that Ayomanor's elbow appeared to land in the field of play before any part of his body hit out of bounds, which led to a question for head coach Brian Callahan about why he didn't challenge the ruling by officials.

"Yeah, you gotta get a foot inbounds too," Callahan said. "We didn't have a clean look at whether his foot was down as well. An elbow doesn't equal two feet so his foot would've had to come down as well. The call from upstairs was that it wasn't worth challenging."

The problem with Callahan's answer is that the NFL rulebook doesn't back up his claim. Per the rules, a pass is complete if a player secures the ball and "touches the ground inbounds with both feet or with any part of his body other than his hands."

An elbow would qualify as another part of the body. That doesn't mean that the Titans would have won a challenge or won the game, but the explanation from the coach was based only on what the league's rules say and it was incorrect.

Callahan was not asked a followup to clarify his answer on Sunday. He'll likely field one on Monday because it appears that he and his staff had a major lapse in the heat of the moment.