RENTON, Wash. -- The Seattle Seahawks can point to several reasons why they finished 9-7 and missed out on the playoffs for the first time since 2011.

They couldn't run the ball, their pass protection was an issue again and they tended to take an entire half to get anything going on offense. Their defense couldn't withstand several key injuries and gave up too many big plays even before Richard Sherman and Kam Chancellor went down. Their special teams weren't great even outside of several costly misses from Blair Walsh.

And then there were the penalties ... a record number of them.

"A major issue, probably my biggest regret this season, is how the penalties factored into our season," coach Pete Carroll said at his wrap-up press conference Monday. "We've been in this situation before and we've been able to overcome the issues and our style of play -- it didn't affect us dramatically -- but this year was more of a factor and our margin wasn't as such that we could endure it as well."

The Seahawks led the NFL in accepted penalties and penalty yards while breaking the franchise records for both. Their 148 accepted penalties were 11 more than the next team, Miami, and 65 more than the least-penalized team, Carolina. Seattle's 1,342 penalty yards were 188 more than what Miami lost and almost double the 682 of Carolina, also the league's least-penalized team in terms of yardage.

Seattle's 148 penalties topped the previous franchise record of 138 (2011) while the 1,342 penalty yards shattered the old mark of 1,183 (2013).

You get the picture: it was really bad.

And it was across the board, with 60 penalties on offense, 65 on defense and 23 on special teams.

"I'm pissed about that, man. I'm pissed about it. I really am," Carroll told 710 ESPN Seattle. "It was the factor this year that in the degree of difficulty we were dealing with, there wasn't enough margin. There's an area there that we can get so much better in. But once you're in the middle of it, it's really hard. We have to go back, we have to make it a better emphasis and count on this margin maybe being close again. We can't let this be the factor."

Here's a closer look at Seattle's penalty problem in 2017.

Worst game: The Seahawks committed 16 accepted penalties for 138 yards in a 17-14 loss to Washington in Week 9. That penalty total was one off the single-game franchise record set in 1984. "We've had enough penalties already in this season where you could say one of these games, it's going to jump up and bite you," Carroll said afterward, "and that’s exactly what it felt like today."

Worst offenders: Right tackle Germain Ifedi and defensive lineman Michael Bennett. Ifedi was the most penalized player in the NFL, according to ESPN charting. His 16 accepted penalties (which didn't count four more that were either negated or declined) led the league by three while Bennett was tied for third-most with 12 accepted penalties (he had 15 in all).

Ifedi had particular trouble with false starts, sometimes moving early in an attempt to get a split-second head start in pass protection as opposed to reflexively jumping. The breakdown of his 20 total penalties: nine false starts, eight holds, two unnecessary roughness penalties and one for unsportsmanlike conduct. Of Bennett's 15 total penalties, 13 were for either offside, encroachment or neutral-zone infraction. A facemask and unnecessary roughness were the other two.

Most costly penalty: Take your pick between two from Seattle's season-ending 26-24 loss to Arizona. A third-quarter screen pass to Thomas Rawls got Seattle to Arizona's 25, but he was flagged for taunting at the end of the play. That pushed the Seahawks back 15 yards and out of field goal range, leading to a punt. Ahead 24-23 in the fourth quarter, Seattle's defense was about to get off the field with Arizona throwing incomplete on third down, but a no-doubt-about-it late hit from Bobby Wagner extended the drive. The Cardinals went on to kick the go-ahead field goal.

This is by no means a new problem for the Seahawks. They also led the league in penalties in 2013 and 2014 -- when they went to back-to-back Super Bowls -- and were the second-most penalized team in 2011. The Seahawks still ranked 11th in penalties in their least-penalized season under Carroll, which was 2010.

Not only was the problem more pronounced in 2017, but the Seahawks didn't have the talent to overcome all their penalties like the 2013 and '14 Super Bowl teams did. That's what Carroll meant when he made several mentions of Seattle's lower margin for error.

Carroll was adamant that it will be a greater point of emphasis. But it's been such a long-standing issue for his Seahawks that it's only natural to be skeptical about the difference that will make.

"That’s a major aspect of us to change," Carroll said. "I'm clear on how I'm going to go about that and it's going to start way back to the first day [of the offseason program], April 16, and we'll make a change there. It has to happen because I don't know that our margins are going to be as big as they’ve been in years past. Maybe they will, maybe they won't."