ST. LOUIS -- Robert Griffin III had his moments. The St. Louis Rams, though, have what counts most of all -- a win.

Sam Bradford threw for 310 yards and three touchdowns, Danny Amendola caught 15 passes for 160 yards, and the Rams rallied for a 31-28 victory over RG3 and the Washington Redskins in their home opener Sunday.

"The dome was rocking, and it should be in a couple of weeks when we get back," Amendola said. "It was a good game. It came down to the wire, came down to the last kick."

Steven Jackson sat out most of the last three quarters after drawing an unsportsmanlike conduct penalty for spiking the ball, but Rams coach Jeff Fisher said it was because Jackson had a groin strain and not because he'd lost his cool.

"It had nothing to do with the spike," Fisher said. "His groin was real tight and we just didn't want to subject him to it. I didn't think he'd be 100 percent."

Rams receiver Danny Amendola celebrates after catching a 1-yard touchdown pass against the Redskins during the second quarter Sunday in St. Louis. Teammate Brandon Gibson looks on. (Seth Perlman ~ Associated Press)

Jackson said he thought he'd be able to re-enter the game but said the groin tightened on him.

Griffin led the Redskins (1-1) to a 21-6 lead, but the Rams came back thanks to the pass-catching of Amendola. The receiver tied an NFL record with 12 first-half receptions and caught a 1-yard TD pass to cut the lead to 21-13 at the half.

Amendola was out virtually all of last season after dislocating his left elbow in the opener.

"Obviously it's nice to have him back out there on the field," Bradford said. "He's a tremendous player. We knew going into this game that we were going to try to get him the ball."

Bradford had second-half scoring passes of 34 yards to Brandon Gibson and 1 yard to Matthew Mulligan.

Griffin ran for two touchdowns and passed for a third for Washington (1-1).

The Redskins got a final shot after DeAngelo Hall recovered running back Daryl Richardson's fumble at the Washington 37 with 2 minutes, 40 seconds to go. Josh Morgan was called for unsportsmanlike conduct for throwing the ball at Rams cornerback Cortland Finnegan after a 7-yard catch on third and 8 to the Rams 29, leaving the Redskins with fourth and 16.

Shanahan called for a 62-yard field goal attempt, and Billy Cundiff was wide right and short with 1:13 to go.

"It might have been the first down. It was close enough. It was inches," Shanahan said. "You can't lose your poise. You lose your poise, obviously good things don't happen."

Shanahan thought Cundiff had a shot, reasoning "he kicks the ball out of the end zone" on kickoffs from the 35. Griffin was disappointed, but he understood.

"I thought we were going for it," Griffin said. "But in a dome, 62 [yards] is far, but it's not that far. I was on a knee and I hoped that it would go through."

The Rams took the lead on Bradford's TD pass to Mulligan on the first play of the fourth quarter, and Richardson ran it in on a 2-point conversion for a 24-21 lead. Mulligan had partially blocked Sav Rocca's punt to give the Rams the ball at the Washington 24 four plays earlier.

Griffin, who looked like a veteran in his NFL debut last week in leading the Redskins to a win over New Orleans, scored on runs of 5 and 7 yards. He also threw a 68-yard touchdown pass to Leonard Hankerson.

Jackson spiked the ball after getting ruled short of the goal line on a third-down carry from the 1. It came a play after the Rams successfully challenged a lost fumble call on Jackson.

After that, the franchise's career leading rusher left and spent most of the rest of the game by himself on the sideline with his helmet in hand.

Amendola had a rough start, fumbling after a 13-yard catch on the Rams' first snap, with Josh Wilson returning it 30 yards for his fifth career defensive touchdown. He recovered nicely, matching the first-half NFL record set by the Colts' Reggie Wayne in 2007. He also tied his career-best game total in the process and set a personal best with 133 yards receiving.

The Redskins lost defensive end Adam Carriker and outside linebacker Brian Orakpo to injuries early in the first quarter, while Rams offensive tackle Rodger Saffold was helped off with a right knee injury.

Orakpo and Saffold were hurt on the same play. Orakpo stripped Bradford and Saffold recovered the fumble and carried it seven yards but crumpled to the turf on the tackle.

Noteworthy

* The game was chippy throughout with several skirmishes, especially in the first half with Redskins linebacker London Fletcher called for a personal foul on a sideline hit on Amendola and the Rams' Eugene Sims whistled for hitting Griffin, who appeared to be turning up the field and not running out of bounds.

* Bradford passed for 300 or more yards for the fourth time in his career and threw for three TDs for the second time.

* Rams rookie punter Johnny Hekker averaged 54.3 yards on three attempts.