Guards Brandon Scherff (torn pectoral) and Shawn Lauvao (torn ACL) and receiver Paul Richardson (AC joint) will all require season-ending surgery, Gruden said.
The loss of two starting guards as well as the continued absence of tackle Trent Williams (thumb) means the Redskins need to take some action regarding offensive linemen.
“Obviously it has a huge impact when you lose your two starting guards,” Gruden said. “Hopefully we can sign a couple guys. We’ve got to sign two, maybe three, offensive linemen to get through this.”
Later Monday, the Redskins announced the signing of three offensive linemen: guard Luke Bowanko, guard Jonathan Cooper and tackle Austin Howard.
As far as the return of Williams, who has a dislocated thumb and missed this past week’s game, Gruden wasn’t sure how much longer his Pro Bowl tackle will be out.
“Hoping two games tops, but that’s being optimistic,” he said.
Richardson has played in seven games this season, including four starts, and has 20 receptions for 262 yards and two touchdowns. He had 44 catches for 703 yards and six touchdowns a year ago.
Gruden said Richardson has had the shoulder problem for a while.
“Paul has been dealing with this all year,” Gruden said. “He toughed it out for eight weeks, (but) the pain has been bothering him so much he has to get it fixed.”
The Redskins have a number options to replace Richardson, including Michael Floyd, who has played in five games for the Redskins this season but has just one reception.
The Redskins play a road game against the Tampa Bay Buccaneers this week after losing to Atlanta 38-14 on Sunday.
–OT Moses Morgan (knee) is day-to-day, leaving another potential problem spot in the offensive line.
–QB Alex Smith was the Redskins’ leading rusher on Sunday, with just 22 yards. He has 119 yards on the ground for the season.
–RB Adrian Peterson had nine carries on Sunday but gained just 17 yards, an average of 1.9 yards per carry. A week earlier he had rushed for 149 yards.
–WR Maurice Harris had a season-high 10 receptions for a season-high 124 yards on Sunday against the Falcons.