"In terms of the way they checked out, signs are pointing in a positive direction," Rams coach Sean McVay said after the 33-31 win at CenturyLink Field. "They were able to have a normal conversation, just seeing them in the locker room and I know they wanted to come back, but ultimately we want to be smart with those things."
After the game, Kupp told teammates he was "good" when asked how he felt as he walked out of the locker room.
But Cooks' and Kupp's injuries leave the Rams with a shortage at the position if they are unable to clear protocol before a Week 6 matchup against the Denver Broncos. Backups Josh Reynolds, a second-year pro, and rookie KhaDarel Hodge took over in their absence.
"I was pretty prepared, but there's always the anxious feeling," said Hodge, an undrafted free agent from Prairie View A&M who began the season on the practice squad. "A little butterfly the first snap until you get some contact. But I wasn't really nervous because I prepared myself very well."
The Rams already have placed backups Pharoh Cooper and Michael Thomas on the injured reserve following a Week 1 victory against the Oakland Raiders. Cooper underwent surgery to repair an ankle injury and Thomas is dealing with a hip injury.
Against the Seahawks, Reynolds, a fourth-round pick from Texas A&M, finished with two catches for 39 yards and rushed for 10 yards on one carry. Hodge had one catch for 14 yards.
"That's what we call a unit," receiver Robert Woods said. "Where guys come in and still make plays -- big-time plays."
Cooks suffered the concussion in the second quarter after he caught an 18-yard pass that he went on to fumble when he took a hit by safety Tedric Thompson. The play was negated by a defensive holding penalty. Cooks laid on the turf as he was tended to by the training staff, before he jogged off the field.
Cooks, who has caught 26 passes for 452 yards and a touchdown this season, did not record a catch against the Seahawks.
Kupp was evaluated for a concussion at halftime before he was ruled out. He caught six passes for 90 yards and a touchdown against the Seahawks and has 30 catches for 438 yards and five touchdowns this season.