SEATTLE - It took a trio of relative unknowns to wake up the Seattle Seahawks.

J.D. McKissic took the second carry of his career 30 yards for a touchdown and Bobby Wagner scooped up Marcus Smith's forced fumble and rumbled 21 yards for a score in a 13-second span late in the third quarter, and the Seahawks beat the Indianapolis Colts 46-18 on Sunday night.

Justin Coleman added a 28-yard interception return for a TD in the first half and Seattle overcame a sleepy first 30 minutes from its offense to finally put away the Colts.

McKissic was once cut by Atlanta, but his athleticism earned him a spot in Seattle. Coleman was deemed expendable by New England and was acquired in a trade just before the start of the regular season. And Smith, who finished with 1 1/2 sacks, was a former first-round pick who was a bust with Philadelphia.

Their big plays turned boos that cascaded down at halftime with Seattle trailing 15-10 into cheers in a hurry. CenturyLink Field was left shaking after Wagner scooped up Smith's forced fumble against quarterback Jacoby Brissett and weaved through tacklers for Seattle's second defensive score and a 32-18 lead.

Russell Wilson threw two touchdown passes and two interceptions, but his most important play was a 23-yard run in the third quarter to give Seattle an 18-15 lead. Adam Vinatieri pulled the Colts even at 18 as the Colts capitalized on Wilson's second interception. Graham dropped a catchable pass and it was intercepted by Malik Hooker , his third straight game with an interception.

But Seattle answered with a 75-yard drive that was capped by McKissic's touchdown sprint. Wilson added TD passes of 6 yards to Luke Willson and 27 yards to McKissic in the fourth quarter and the Seahawks outscored Indianapolis 36-3 in the second half.

Seattle's win came with a big blow in the final minutes when starting running back Chris Carson sustained a left leg injury. Trainers immediately placed an air cast on Carson's leg and he was carted off the field.

Brissett threw an 18-yard strike to Donte Moncrief late in the first half to give the Colts the lead. Brissett was 16 of 29 for 157 yards and was sacked three times. The biggest play turned out to be Smith's sack, knocking the ball from Brissett's hands just before his arm moved forward as Seattle suddenly took a 14-point lead.