Andy Lyons, Getty Images
The Colts' Reggie Wayne motions to the crowd after catching a touchdown pass during Indianapolis' victory over the Broncos on Sunday.

INDIANAPOLIS — The Indianapolis Colts spent one quarter trying to figure out Denver's confounding ground game.

Peyton Manning spent the next three confusing the Broncos' defense.

Manning led the Colts to six scores on his final eight possessions, rallying Indianapolis from an early 10-point deficit to an impressive 38-20 victory Sunday — giving the Broncos one more anguishing chapter in this lopsided rivalry.

"They tried to break our will," Colts cornerback Marlin Jackson said, referring to Denver's steady diet of powerful runs.

Instead, the Colts eventually broke the Broncos with some nifty adjustments and surprise reinforcements.

Eight-time Pro Bowl receiver Marvin Harrison left in the second quarter with a bruised left knee and did not return. Outside linebacker Rob Morris was carted off the field just before halftime with a sprained left knee. Former Pro Bowl safety Bob Sanders (ankle) and running back Joseph Addai (shoulder and back) couldn't finish the game, either.

The patient Super Bowl MVP never fretted, even without his most reliable target — Harrison.

Manning completed 20-of-27 for 193 yards with three touchdowns, and Addai gave the Broncos a dose of their own medicine by carrying 19 times for 136 yards and another score before leaving early in the fourth quarter.

The result: Indianapolis is now undefeated for the third straight September, still has the league's best September record (18-2) since 2002 and extended its league-best win streak to nine games when the playoff wins included.