Rookie running back Todd Gurley needed only two games to show why he was so highly coveted by the St. Louis Rams.

The rookie rushed for 146 yards -- 144 in the second half -- on 19 carries Sunday in his second NFL game to lead the visiting Rams to a 24-22 upset of the previously undefeated Arizona Cardinals.

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Less than a year removed from season-ending ACL surgery at the University of Georgia, Gurley flashed the difference-making skills that led St. Louis to select him with the No. 10 overall pick in this year's draft -- even though he wasn't fully healthy at the time.

On Sunday, Gurley started slow with two yards rushing on four first-half carries, a somewhat ominous sign following last week's pedestrian debut that netted nine yards on six rushes.

But in the second half, Gurley ripped off four runs of at least 20 yards, including a 52-yard burst that set up Nick Foles' second touchdown pass to Tavon Austin for a 24-15 lead with just over eight minutes to play.

Gurley also displayed the poise of a veteran as the Rams played keep-away in the fnial two minutes of the game. After going down to stay inbounds on a short run, he broke free down the left sideline and had a possible path to his first NFL touchdown but opted to slow up and go to the turf to allow St. Louis to run out the clock and seal the victory.

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