Coaches say there are five key plays that decide a football game. The Seahawks blew at least eight in Super Bowl XL -- costing them as many as 20 points -- and lost to the Steelers 21-10.
In many ways, this was the most painful of Super Bowl losses. For two weeks, the Seahawks were confident about their ability and game plan, and they were right. For a while, they looked like the better team. Matt Hasselbeck came out and moved the football with quick passes to Darrell Jackson in the first quarter. Receivers were open. The defense continued its shutout streak in the first quarter, holding the Steelers' offense to three three-and-out possessions. Against the Redskins and Panthers in the NFC playoffs, the Seahawks' quick, undersized defense had a combined seven three-and-outs to start playoff games.
Then came the mistakes, and the Seahawks didn't have answers.
"We had a great week of practice, and we did things very, very well," coach Mike Holmgren said. "There were some guys who made some great plays and great catches out there, but we did drop the ball uncharacteristically. And the thing that bothers me as much as anything was the penalties. We had a touchdown called back. We had a catch down to the 1-yard line called back. We had a pretty good punt return called back, and that's tough. You can't overcome those things."
Holmgren teams normally are among the best at not committing penalties. In Super Bowl XL, the Seahawks had seven infractions for 70 yards, and they all came at key times and left the Seahawks scratching their heads. In the regular season, Seattle averaged six penalties per game but for far fewer yards.
"That's the way it is when you are going against the world," Jackson said. "It seemed like all our big plays were overturned or called back. When you are going against the world, that's the way it is."
Jackson was involved in four wacky plays. He started the game red-hot, with five catches for 50 yards, the first five-catch first quarter in Super Bowl history. But worlds started colliding for Jackson.
In the first quarter, the Seahawks had a third-and-6 at the Steelers' 41. Hasselbeck hit Jackson with an 18-yard completion to the Steelers' 23, but it was called back by a holding penalty against guard Chris Gray. That killed a potential scoring drive and led to a punt.
Later in the first quarter, Hasselbeck threw a 16-yard touchdown pass to Jackson, but Jackson had shoved safety Chris Hope slightly with his right hand and drew an interference penalty. He couldn't believe it.
"I don't think I touched him," Jackson said. "I was very surprised when I got the call."
Replays showed Jackson's hand on Hope. It's safe to say the officials were calling them close in Super Bowl XL. The play cost the Seahawks four points when they failed to get a first down after the penalty and settled for a 47-yard Josh Brown field goal and a 3-0 lead.
Jackson caught two balls out of bounds in the final minute of the first half, one that could have been a touchdown and another that would have put the ball inside the 5. Instead, they settled for a missed 54-yard field goal attempt at the half and trailed 7-3 at the break.
"The ball hung up a little bit on the one throw, but maybe [I] could have done something to stay in bounds," Jackson said.
Joey Porter of the Steelers must have been smiling. During the week, in response to what he thought was a verbal slam against the Steelers, Porter called Jerramy Stevens soft, unwilling to block, a first-round bust and his "huckleberry." In Super Bowl XL, Stevens dropped three key passes.
One drop would have been a 20-yard completion to the Steelers' 27 on a third down early in the second quarter when Stevens had gotten behind a safety. Another would have been a 29-yard completion to the Steelers' 8 on the first possession of the third quarter. He dropped another one with four minutes left in the third quarter. After the game, reporters wondered whether the national attention affected his game.
"It doesn't matter what anyone thinks," Stevens said. "The bottom line is I didn't get it done. It was frustrating because we didn't play the way we were capable of playing. Obviously, it was frustrating. We just lost the Super Bowl."
Fittingly, Stevens -- who finished with only three catches for 25 yards and a touchdown -- had Porter standing over him while Stevens was on the ground at the end of the game.
"I don't need to think of anything," Stevens said of Porter. "He is on the winning team, and that's all that matters."
However, Stevens can't take the blame for the play that might have been the most critical of the game. With Seattle trailing 14-10 late in the third quarter, Hasselbeck was directing what looked to be a 98-yard scoring drive. Stevens caught a 17-yard pass to the Steelers' 2, but right tackle Sean Locklear was called for his second holding penalty of the game.
The drive came to an end when Hasselbeck didn't spot cornerback Ike Taylor on a throw to Jackson. Taylor made the interception, thwarting the scoring opportunity and preserving the Steelers' lead. Four plays later, Antwaan Randle El hit Hines Ward with a 43-yard touchdown pass on a reverse.
If the penalties and drops weren't enough, kicker Josh Brown missed two long field goals -- for 54 and 50 yards. He was 5-for-8 on long kicks this year. The Super Bowl attempts -- had he made them -- could have kept the Seahawks in the game.
"I'm not sure they were mental mistakes as much as just mistakes," Hasselbeck said of the Seahawks' offensive woes. "I guess it wasn't our day that way. You can't make the mistakes we made and expect to win the game against a good team like that."
This loss won't be easy to get over for the Seahawks and Holmgren. Remember, when Holmgren and the Packers lost the Super Bowl to the Denver Broncos, it took him a month to get out of the funk. He punished himself mentally for what he thought was his inability to convince the Packers that the Broncos were that good.
That's one reason he felt so good about his team's chances in this game. His team peaked during Super Bowl week. Wednesday's practice was one of the team's best and sharpest. The passing was crisp. The tempo was phenomenal. The defense was flying around the field, and that carried over to a first quarter in which the Seahawks defense pitched a shutout.
But the penalties and the dropped passes and the questionable officiating calls nagged at Seattle all game. Holmgren was so mad about Ben Roethlisberger's controversial 1-yard touchdown run that he spent as much time arguing with officials while heading to the locker room at halftime as he did talking to ABC's Suzy Kolber.
"I'm more disappointed in how we played in certain areas," Holmgren said. "I think we were careless with the football, and we had too many penalties. And that combination against a great team like the Steelers is not a good combination, so I think that's pretty much the story of the game."
Hasselbeck admitted his interception in the fourth quarter came when he was trying to force a pass because the Seahawks were trailing and were trying to make a play. It killed him to think how many points the Seahawks -- the league's highest-scoring offense -- left on the field.
"There were a lot of them," Hasselbeck said. "We've done a great job of scoring this year and scoring in the red zone. We had a touchdown taken away from us. We had a ball on the 1-yard line. That's unfortunate."
It cost the Seahawks their first Super Bowl.
John Clayton is a senior writer for ESPN.com.