The Seahawks started the game well and moved the ball courtesy of a big penalty call on cornerback Jonathan Joseph as he was adjudged to have interfered illegally with a pass for Sydney Rice for 30 yards.
However, inside the red zone the Texans defense tightened up and got pressure on Russell Wilson led by JJ Watt, forcing the visitors into a field goal that Stephen Hauschka dispatched through the posts from 48 yards.
The home side responded to going behind as quarterback Matt Schaub got them moving and early in the second quarter they took the lead when he hit Garrett Graham down the seam for a 31-yard touchdown.
Houston extended their lead with another methodical drive by Schaub, as he dissected the Seahawks' defense to lead his team to the red zone and then found running back Arian Foster with a short pass; he went in for the score from five yards out.
Matters got worse for Seattle when running back Marshawn Lynch fumbled the ball and Brian Cushing picked it up for the home side. Schaub could not find the end zone on this occasion, forcing Randy Bullock into a 22-yard field goal that he nailed between the posts.
Bullock added another field goal just before the break from 42 yards to extend his side's lead to 17 points. After half time, the Seahawks reduced their arrears by three points as Hauschka added a field goal from 39 yards.
In the fourth quarter the visitors got themselves back into the game with a fine drive orchestrated by Wilson, who dragged his team to the red zone with a series of running and passing plays before tossing to Lynch, who went in for the touchdown to make the score 20-13.
Seattle levelled the scores late in the fourth quarter when Schaub threw a pass short for Graham and the throw was picked off by Richard Sherman, who ran the ball back to the end zone for a 51-yard touchdown, forcing the contest into overtime.
Both defenses battled to keep each other of field goal range and succeeded until Wilson finally put a drive together for the Seahawks, which put them in Hauschka's range. He duly delivered with the kick, sending it through the posts from 45 yards to seal a victory for Pete Carroll's side.