With 1:09 left in the first quarter, the Redskins committed their first turnover of the season on offense, as tight end Chris Cooley fumbled after teaming with quarterback Jason Campbell (18 of 26 for 208 yards) on an 11-yard reception.
On Washington's first possession of the second quarter, Campbell couldn't secure a poor snap from center Casey Rabach, and defensive end Chris Long came up with the ball at the Rams 49-yard line.
Then came Washington's biggest blunder. On first down at the Rams 16-yard line, defensive end Clifton Ryan tipped Campbell's pass high, and Kendall grabbed the ball and started to run.
The 13-year veteran, who is listed at 6 feet 5 and 286 pounds, didn't get far. Rams linebacker Pisa Tinoisamoa separated Kendall from the ball, Atogwe scooped it up at the Rams 25 and went untouched for the touchdown.
"It's hard for me to know that I let down the 52 other guys in this locker room, the coaches, owners, the fans," Kendall said. "If I knock that ball down, whether we make the field goal or not, we win the game today."
Kendall's blunder, though, was not solely responsible for the Redskins' first loss in five games, Portis said. Overconfidence could have been the biggest problem.
"I think the headlines got good," Portis said. "Guys started high-fiving and yelling, 'We here!' "
Previously winless St. Louis takes advantage of mistakes and breakdowns from Washington to win on Josh Brown's field goal as time expires.
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