The 2026 NFL season begins the weekend of Sunday, Sept. 13, and the Chiefs will take every day they can get. Their clock has already started.

Although former NFL QB Brian Hoyer wouldn't wish an ACL injury on anyone, grinding through the rehab process made him mentally tougher.

With the Packers facing a possible ACL tear for Micah Parsons, here’s a look at other recent NFL players to suffer the injury and when they returned.

Chiefs quarterback Patrick Mahomes gets his ACL surgery performed by Dr. Daniel E. Cooper, the Cowboys' team physician.

On Christmas Eve 2011, just 30 yards shy of a fifth consecutive 1,000-yard season to begin his NFL career, Peterson tore his ACL. And in one of the greatest comebacks in sports history, Peterson didn’t just return in time for the season-opener; he also rushed for 2,097 yards and captured NFL MVP honors.

The theme of the 2025 NFL regular season has been one of extreme unpredictability: Super Bowl favorites performing below usual standards, unexpected comebacks and breakout teams taking the league by storm.

The NFL has implemented rule changes in recent seasons aimed at reducing lower-body injuries, including the ban on hip-drop tackles. Still, experts say the nature of the sport, built on speed, power, and rapid changes in direction, means ACL injuries remain a risk.