SEATTLE -- After losing four fourth-quarter leads last season, then melting down in the Florida heat last week, this would have been the worst loss of all for the Seattle Seahawks.

The team's defense saved the day.

"I was thinking, 'Oh my goodness, here we go again,' " coach Mike Holmgren said after the Seahawks nearly blew a 21-0 halftime lead Sunday, holding on to beat Atlanta 21-18.

Shaun Alexander ran for 144 yards and a touchdown and Matt Hasselbeck threw for 281 yards and two more TDs. Still, it was the defense that won it for the Seahawks, shutting down the Falcons after Atlanta got the ball back with 2:39 left at its 27.

Bryce Fisher sacked Michael Vick on third down, then Andre Dyson knocked down a pass intended for Michael Jenkins from Matt Schaub, who twice replaced Vick late in the game when the Atlanta QB felt his left leg cramping after a 32-yard run. Fisher fell on Vick as he fell a yard behind the line of scrimmage.

"At the end of the year, I'm telling everybody that's the greatest rush ever made," said Fisher, who signed as a free agent from St. Louis and is one of seven new starters on the Seattle defense. "It was a sack anyway, it just helped me that he laid down."

The game left both teams at 1-1.

Seattle lost in the heat of Jacksonville as Hasselbeck had three turnovers in the fourth quarter, and Atlanta had an emotional Monday night win over Philadelphia. The Falcons played the first half like that game had taken everything from them with a short week and a cross-country trip added in.

Vick twice missed Jenkins wide open for an apparent TD, once in the first half and again in the second. He finished just 11-of-19 for 123 yards and had 11 yards in seven carries aside from that long scramble.

Overall, Seattle outgained Atlanta 428-223. In the second quarter alone, the Seahawks had 13 first downs to none for the Falcons and outgained them 219-13.

"They played a great defensive scheme," Vick said. "They did some things that threw us off-balance."

Most important, they scored three times on drives that covered 75, 68 and 80 yards. The scores came on a 6-yard pass from Hasselbeck to Joe Jurevicius, a 14-yard run by Alexander and a 35-yard pass to tight end Jerramy Stevens with 28 seconds left in the half.

In fact, the best Atlanta player in the first half was rookie punter Michael Koenen, who played last year at Western Washington in Bellingham, about 75 miles north of Seattle. He kept pinning the Seahawks deep.

"They played the way we like to play," Falcons coach Jim Mora said, "with great tempo and they were moving the ball and they were playing inspired defense. No excuses on our side. We've got to play better, we've got to start faster."

Instead, they started after intermission, cutting it to 21-10 with two scores early in the third quarter: a 5-yard pass from Vick to Brian Finneran and a 30-yard field goal by Todd Peterson. Meanwhile, Hasselbeck threw five straight incomplete passes to start the quarter.

For a while the game stabilized.

The Seahawks ate up more than seven minutes of the fourth quarter with a drive that took them from 9 to the Atlanta 18 before they were set back by three penalties and Bobby Engram finally lost a fumble on a third-down play.

"They were bringing four or five and it confused us a little," Stevens said. "We made our adjustments and we were able to start moving the ball again."

Still, that turnover gave Atlanta another shot.

Vick, who had 11 yards on seven carries to that point, scrambled for 32 yards and found Finneran for 11 more. He then left with the ball at the Seattle 5-yard-line, holding his left leg. As trainers worked on Vick on the sideline, Schaub's third-down pass for Jenkins was incomplete, but Dyson was called for interference.

T.J. Duckett then scored from the 1 and Schaub found Alge Crumpler for the 2-point conversion to make it 21-18 with 3:58 to go.

Notes

• Atlanta WR Dez White injured his knee in the second quarter and lay on the field for several minutes. He later returned to the game.
• Seattle WR Alex Bannister left after injuring his right collarbone -- the same bone he's broken twice in the last year. Holmgren said X-rays were inconclusive and Bannister said it was not as bad as his previous injuries.
• The Seahawks beat the Falcons 28-26 in the final regular-season game here last year, with Vick resting in the second half.