"We have a lot to prove every time we step out and this is just another stepping stone, the next team in our way," said Seattle safety Earl Thomas, a key to the Seahawks' top-ranked defense.
That opponent is Houston, and the Texans are no slouches on defense either. Houston (2-1) is second to Seattle in yards allowed in the NFL.
The Seahawks are 3-0 for the sixth time in franchise history and the first time since 2006. Their defense is also the stingiest on the scoreboard, limiting teams to just nine points a game.
Coach Pete Carroll is using the experience he gained in leading so many outstanding teams at Southern California to help teach the Seahawks how to handle their early success, and outside expectations.
"We had those No. 1 rankings year after year after year," Carroll said of his time at USC. "You become comfortable with that and that's where you want to be. You want to get to the point where you understand why people talk about you as they do, and then you want to constantly remember that you live up to that."
Naturally, a key to Seattle's early success has been that staunch defense, which has been a force at forcing turnovers. The Seahawks are tied for second with a plus-6 turnover differential.
"It's a winning formula in itself," Carroll said. "We do it because it's the single-most important factor to winning for us. Our numbers have kind of proven that out."
Both teams have good reason to feel great about their defenses, but recognize they'll have to improve on offense to contend for a championship.
Seattle quarterback Russell Wilson said going against the top defense in the NFL every day in practice has helped the offense get better. He hopes that will help in dealing with Houston this week.
"This game's going to be a huge game," Wilson said. "It's one of the teams that obviously is a 'Super Bowl contender,' and is a team that's got a lot of talent and everything."
Five things to know about the Seahawks-Texans game:
CARROLL & CUSHING: Houston linebacker Brian Cushing played for Carroll at USC from 2005-08.
"He was ... a very influential person to me at a critical stage in my career and in my life," Cushing said. "A guy that's helped me tremendously to grow up as a person and a football player."
Carroll had plenty to say about his former player, and joked about how hyper-competitive he has always been before raving about his play.
"Really one of the best players we ever recruited," Carroll said. "He had such a great all-around ability that he could do a ton of things. The fact that he's continuing to do it is no surprise to me. He's a great team member."
SECOND(ARY) TO NONE: Perhaps the biggest strength of Seattle's defense is its secondary. Carroll liked Houston coach Gary Kubiak calling him a "secondary guy" this week.
"If you've got guys that can play out there and hang up play after play after play with any receiver you throw out to them, it allows you to do things defensively scheme-wise that really is an asset," Carroll said. "I've been a defensive back guy forever."
Seattle's defensive backs are not only skilled, they're big. Three of the four starters in the secondary are 6-foot-3 or taller. Kubiak said Seattle's safeties "look like linebackers."
BADGER BROTHERS: Wilson transferred to Wisconsin from NC State in 2011. Houston defensive end J.J. Watt's last season with the Badgers came in 2010; he declared for the draft after his junior year.
Wilson has since met Watt and said the two had a talk about what might have been at the Pro Bowl last February.
"Me and him were just joking that if he had stayed his senior year, we probably would have won the national championship," Wilson said. "I missed playing with him."
Watt, the 2012 Defensive Player of the Year, agreed.
"It sure would have been fun," Watt said. "I wish I would have known he was coming."
MARSHAWN'S SUCCESS: Seattle's Marshawn Lynch has piled up more yards rushing than any player since Week 9 of 2011 with 2,741 yards. Lynch leads the NFL with 16 games with at least 100 yards rushing since 2011.
He has ran for at least 100 yards in 16 of his last 28 games and set a career high by posting 10 100-yard games last season.
Lynch, who ran for a career-best 1,590 yards in 2012, has 210 yards rushing with two touchdowns this season.
ANDRE'S ABLE: Houston's Andre Johnson had one of the best games of his career in his only meeting with Seattle. He had 11 receptions for 193 yards and two scores in the Texans' 34-7 win in 2009.
Johnson averages 81.6 yards receiving a game, best in NFL history for players with at least 100 games. He's been particularly good against the NFC with 16 receptions for 285 yards in his last two games.
Johnson has a bruised shin, but Kubiak said he's likely to play this week.
AP Sports Writer Tim Booth contributed to this report from Seattle.