SEATTLE — With the Seattle Seahawks offense starting slowly against the St. Louis Rams on Sunday, it fell to the defense to give the team a lift.

Seattle linebacker Malcolm Smith did all that and more.

On St. Louis’ first offensive series, and on a second-and-14 play from the Rams 33, Smith intercepted a pass and returned it 37 yards for a Seahawks touchdown. It gave Seattle an early 7-0 lead and had a CenturyLink Field crowd of 68,264 going crazy with joy.

As important as Smith’s touchdown was emotionally to the Seahawks, it was critical on the scoreboard, too. It was the only TD by either team until midway through the third period when Seattle running back Marshawn Lynch finally reached the end zone to give the Seahawks a 20-3 margin. Prior to Lynch’s touchdown, Seattle’s offense had seven possessions resulting in five punts and two field goals.

On the interception play, the Seahawks dropped into zone coverage with Smith near the middle of the field. St. Louis quarterback Kellen Clemens threw a pass intended for tight end Jared Cook, but it was high and deflected off Cook’s up-stretched hands.

The ball came right to Smith, who started right on his return and then curled back to the middle of the field. He went untouched to the end zone.

“Honestly, it kind of just came right into my hands,” Smith said. “And obviously I was focused on the ball. It came right to me and I was fortunate to catch it.

“Every time I touch the ball, I want to get to the end zone,” he added. “So it feels good helping the team out.”

The irony is that Smith had a similar interception last week against Arizona. Unfortunately, that return was stopped at the Cardinals 3-yard line, and the Seahawks ended up not scoring when kicker Steven Hauschka missed a short field goal.

Smith was fully aware of what happened last week, “and I wasn’t going to let that happen twice,” he said.

As Smith and his teammates celebrated in the end zone Sunday, the Seattle crowd reacted with deafening cheers and the Seahawk sideline erupted in jubilation. It was exactly the spark the team needed in a pivotal game, with the Seahawks going on to finish with a 13-3 regular-season record and the top NFC seed in the upcoming playoffs.

“That’s the energy we were waiting for,” Smith said. “It was a great play for us.”

“I’m so proud of Malcolm,” said Heath Farwell, a fellow Seattle linebacker. “He’s stepped in and played well, and he got an interception for a touchdown. He kind of got the ball rolling and the crowd was into it.”

Smith has been a sometimes starter for the Seahawks this season, including three of the first four games when linebacker Bruce Irvin was sitting out a suspension (Smith missed one of those games with an injury). He then became a starter again when Bobby Wagner missed two games with an ankle injury, and once more in the last three games in place of injured K.J. Wright.

“Malcolm continues to come through,” said Seattle coach Pete Carroll. “He’s been a great asset for us. Whatever we’ve asked him to do, he’s done well.”