Allen Park — Lions defensive end Jason Jones missed practice Wednesday due to a family emergency, and coach Jim Caldwell doesn't know whether or not he'll be available for Sunday's game against the New England Patriots.

"I'm not certain, to be honest with you," Caldwell said Thursday.

The 28-year-old Jones starts in the Lions' five-man defensive end rotation. Primarily a run stopper, Jones has 12 tackles and two sacks this season.

If Jones is not available Sunday, George Johnson or Darryl Tapp would likely replace him in the starting lineup opposite Ezekiel Ansah, and rookie fourth-round pick Larry Webster could have a role behind Devin Taylor, too.

For now, Caldwell said he's hoping Jones can return "in due time," but he doesn't know when that will be.

"I'm not certain of that, but he's taking care of things and he'll be back shortly," Caldwell said.