What happened: Dallas will place All-Pro guard Tyler Smith on injured reserve, making him unavailable for at least four games. He played through the problem for most of training camp before surgery became necessary.

Why it matters: The absence removes a key starter from the Cowboys' offensive line to begin the regular season. A return at the short end of the estimate would limit the disruption once he becomes eligible to leave injured reserve.

What to watch: Smith is scheduled for surgery Tuesday. His recovery afterward will determine whether the Cowboys' four-week expectation holds.