Los Angeles Rams running back Todd Gurley was limited at the end of the season and in the playoffs due to arthritis in his left knee, according to The Athletic's Jeff Howe.
The Rams had blamed soreness and inflammation for sidelining the 24-year-old workhorse back.
Head coach Sean McVay said at the NFL Scouting Combine earlier this week that Gurley, who suffered a torn left ACL in 2014, would not need surgery.
McVay also said that stem cell treatment isn't currently being considered, but he didn't rule it out as an option.
The NFL has requested more information from the team about why Gurley was left off the Super Bowl injury report, a league source told Field Level Media.
Gurley largely gave way to C.J. Anderson in the postseason, but the company line from the Rams centered around McVay taking the blame for not getting Gurley more involved.
Gurley missed the final two regular-season games, dealing with the undisclosed knee problem, after rushing for 1,251 yards and 17 touchdowns in 14 games. He also caught 59 passes for 580 yards and four scores.
Gurley returned for the playoffs -- with 16 carries for 115 yards against Dallas -- but had only a combined 14 carries and two receptions in the NFC Championship Game and Super Bowl LIII.
Gurley rushed just 10 times for 35 yards in a 13-3 loss to the New England Patriots.
Anderson, who signed with the Rams for the final two regular-season games, had 46 postseason carries. Gurley had 30.
Gurley led the NFL with 21 touchdowns and 17 rushing scores during the regular season. He notched his third 1,000-yard rushing season in four years since the Rams took him with the 10th overall pick in the 2015 NFL Draft.
--Field Level Media