NFC West Week 7 decisive moment

Arizona Cardinals running back Tim Hightower had gashed the NFL's second-ranked run defense for 59 yards on six carries.

His runs for 9, 5, 1, 7, 24 and 13 yards were giving Arizona a chance against the Seattle Seahawks in Week 7 despite shaky play from a rookie quarterback.

Then the ball came loose. A pileup ensued. Hightower couldn't get the ball back.

The fourth-year running back had lost a fumble for the third time in six games this season and the seventh time in his past 20 regular-season games. Momentum turned against Arizona. The Cardinals trailed only 3-0 at the time, but they lost 22-10.

The moment proved decisive for Arizona and it could become decisive for Hightower as well. The Cardinals appear closer to replacing Hightower in the starting lineup with 2009 first-round choice Beanie Wells, who hasn't lost a fumble in four games this season.

Hightower hasn't gone more than five games without losing a fumble over the past two seasons. He remains valuable to the Cardinals as a runner, receiver and pass protector, but Arizona's margin for error isn't large enough to tolerate lost fumbles.