Joe Flacco sustained a season-ending knee injury Sunday, leaving backup Matt Shaub to assume the controls of a Baltimore offense that scored only one touchdown in Sunday's 16-13 victory.
Flacco tore ligaments in his left knee in the final minute, an injury that will end his run of 122 consecutive starts. Baltimore (3-7) will look to add a backup this week.
The Ravens (3-7) must also make adjustments at running back. Leading rusher Justin Forsett broke two bones in his right forearm while being tackled in the first quarter and is out for the year.
''It's OK,'' coach John Harbaugh said. ''We'll rally behind Matt. We'll rally behind the rest of our running backs, because we're a football team. We are a team, and that's how we approach it.''
Flacco went the distance despite being injured on the first play of the last series, which ended with a 47-yard field goal by Justin Tucker as time expired.
The winning score came after Rams quarterback Case Keenum was sacked and lost a fumble in his own territory. He completed 12 of 26 passes for 136 yards and a touchdown. Although he wasn't intercepted, Keenum fumbled three times and lost two of them.
Keenum was making his first start with St. Louis after replacing Nick Foles in a move coach Jeff Fisher said was designed to provide a spark to the Rams' struggling offense.
It didn't work. The Rams (4-6) produced only 213 yards and lost four fumbles.
''We're asking a lot of our defense right now when we're not getting a lot out of our offense,'' Fisher said.
Fisher said he intended to stick with Keenum for at least another week, but the quarterback took a hard hit late in the game and was being checked for a concussion afterward.
Other observations from the Rams-Ravens game:
TRENCH TROUBLE: Ten games into the season, the Rams are working with a patchwork offensive line that isn't doing the job.
St. Louis went into the game without rookie starting right tackle Rob Havenstein (calf) and shifted right guard Andrew Donnel to tackle, until he departed with a knee injury that Fisher fears might be serious.
Not surprisingly, the line had trouble containing an aggressive Ravens rush. Baltimore repeatedly penetrated, holding St. Louis to 82 yards rushing, blocking an extra-point kick and using a sack by Courtney Upshaw to set up the winning score.
REDEMPTION: Tucker's third game-winning field goal of the season salvaged an otherwise disappointing day for the normally reliable kicker, who earlier misfired twice from 51 yards - including a try that veered off course with 1:13 to play.
''I don't think I've ever been this upset or mad after hitting a game-winner, but this is kind of unchartered territory for me,'' said Tucker. ''To be able to bounce back like that, though, it's definitely satisfying.''
Tucker, who now is just 2 for 7 from 50 yards or more this season, said a blustery wind played a role in the inaccuracy.
''Our stadium is just a tough stadium to kick in,'' he said. ''I think the wind was anywhere from 12-20 miles per hour at any given time.''
LOSING HIS GRIP: For the longest time Sunday, running back Todd Gurley's 1-yard touchdown in the first quarter was the game's lone TD. But two of his second-half mistakes - a botched handoff from Keenum and a fumble - were recovered by Baltimore.
Gurley took full responsibility for the miscues.
''At the end of the day, I'm a running back,'' he said. ''Hold onto the ball.''
REPLACEMENT PLAYERS NEEDED: As it stands now, Baltimore's backup quarterback is punter Sam Koch.
''We're not real comfortable with that situation, so we'll find one,'' Harbaugh said.
A replacement for Forsett is also forthcoming. After Forsett went out, rookie Javorius Allen took over and finished with 67 yards on 22 carries.
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