The Seattle Seahawks fell to the Denver Broncos 27-24 in their regular season opener Sunday afternoon.

While the Seahawks kept it close throughout the day, mistakes and penalties cost them the ball game in the end.

Here are key takeaways from the Seahawks regular-season opener.

Earl Thomas’ presence is invaluable

Less than a week after ending his holdout, Seahawks free safety Earl Thomas logged his first interception of the regular season. He finished the day against the Broncos with five tackles, three of those solo.

Thomas skipped all offseason activities but returned to the team in time play on Sundays and collect his weekly game checks to finish out his contract in Seattle.

But with Kam Chancellor on the injured reserve and out for the season and Richard Sherman now with the 49ers, the Seahawks desperately needed Thomas’ veteran presence among the new-look Legion of Boom.

Thomas’ experience, leadership and playmaking ability will be tough to replace should he part ways next season when his contract expires.

Seahawks run game still not solidified

Chris Carson won the starting nod on Sunday over rookie first-round draft pick, Rashaad Penny. With Penny out most of the preseason following finger surgery, Carson has handled the majority of Seattle’s snaps.

Running back Mike Davis was inactive against the Broncos, leaving just Carson, Penny and C.J. Prosise to split the carries in the season opener. Carson made the most of his opportunities despite a fumble in the third quarter, completing his outing posting seven carries for 51 yards with a long of 24.

But Seahawks’ run game still remains anemic as Seattle did not score a rushing touchdown in Denver and only managed 64 total yards on the ground.

Will Dissly is a receiving tight end

The Seahawks selected tight end Will Dissly in the fourth round of this year’s draft for his blocking abilities, but it was his receiving Sunday afternoon that has gotten the most attention.

The former Washington Husky finished the game as the team’s leading receiver with three catches for 105 yards and a touchdown – all in the first half.

Dissly connected early with quarterback Russell Wilson for Seattle’s first score of the game. Wilson found Dissly once again later in the quarter for his long of 66 yards.

Turnovers kept the Seahawks alive on Sunday

Free safety Earl Thomas wasn’t the only player with an interception against the Broncos in Denver. Bradley McDougald rose to the occasion not once but twice to keep the Seahawks in the ball game.

Seattle was able to capitalize on the takeaways by putting points on the board after the picks came at critical times during the matchup.

The Seahawks weren’t immune from turning over the ball themselves on Sunday, matching the Broncos 3-3.