Pete Carroll looked like a man who knew he had just thrown the NFL’s most impactful red challenge flag of the 2020 season.

The second half of Sunday night’s game against the Vikings was six minutes old. The purple-clad visitors to Seattle’s CenturyLink Field were up 13-7. And the officials had just ruled that Vikings quarterback Kirk Cousins had thrown an incomplete pass on third-and-17 from deep inside his own territory.

Carroll, the Seahawks’ ageless bundle of coaching energy, hadn’t thrown a challenge flag all season. But his assistants in the booth above told him to fire away. Defensive tackle Damontre Moore had knocked the ball out of Cousins’ hand early, meaning the incompletion actually was a fumble recovered by linebacker K.J. Wright at the Vikings 15-yard line.

When Carroll looked up and saw the replay himself, the 69-year-old didn’t wait for the official announcement. He scooped up the challenge flag, turned to the Seattle sideline and thrust both arms into the air.

His career record on coaching challenges improved by one to 43-49. Only six of his peers have won more: Jon Gruden (76-122), Andy Reid (60-66), Sean Payton (55-67), Bill Belichick (49-73), Mike McCarthy (47-47) and John Harbaugh (47-60).

Two plays later, Russell Wilson threw the second of his three red-zone touchdown passes. Seattle led 14-13. Mike Zimmer’s 13-0 first-half masterpiece against a team that was averaging 35 points a game was gone.

All because of a bean-filled red flag stopped the game and made the officials get it right.

The challenge system began in 1999 with each coach getting two challenges. In 2004, the league added a third challenge if the first two are successful. Turnovers, scoring plays and the last two minutes of each half are monitored by replay officials in the booth.

Some coaches are reluctant to throw the flag. Joe Judge still hasn’t thrown one five games into his rookie season as Giants coach. Matt Nagy is 2-6 in eight tries in 38 games.

Some coaches are notoriously nonchalant in how many times they fire the flag and risk losing timeouts. The Raiders’ Gruden sits atop that list.

Despite a 10-year hiatus as a television analyst, Gruden’s 198 attempts are 76 more than the next closest: Belichick and Payton at 122. Belichick has been a head coach through all but one season of the challenge system.

Gruden went 1-9 on challenges last year. He lost his first seven. When he reached 0-6, reporters wanted to know why he kept firing away.

“We’re going to trust the process,” he said. “So far, I’ve been given the Heisman. I’ve been stiff-armed. I’m like 0-for-27, I think. But when I listen to people in the booth tell me it’s the wrong call, I believe in the process.”

Percentage-wise, Gruden ranks 24th (.384) among the current 32 head coaches. Belichick, the six-time Super Bowl-winning future Hall of Famer, ranks 20th (.402) and is the only coach to lose more than two this season (1-4).

Technically, Judge is last on the list (.000) because he’s yet to launch a flag. The worst among those who have is Bills coach Sean McDermott.

He may be turning the Bills around, but he’s terrible at challenges, going 3-14 (.176). He’s one of three coaches — including Pittsburgh’s Mike Tomlin and Indianapolis’ Frank Reich — to start 0-2 on challenges this season. Reich ranks 28th overall at 4-11 (.267).

Eight coaches are above .500 in career challenges, including No. 8 Mike Zimmer at 20-19, including 1-0 this year.

First-year coaches Matt Rhule in Carolina and Kevin Stefanski in Cleveland are the only coaches not to lose a career challenge. They’re 2-0 through five NFL games. Four other coaches — Philadelphia’s Doug Pederson, Washington’s Ron Rivera, Tampa Bay’s Bruce Arians and Denver’s Vic Fangio — also are a league-leading 2-0 this season.

Ironically, leading the career challenge percentage among active coaches is Jacksonville’s Doug Marrone. He’s 23-16 on challenge calls and 38-49 in wins and losses after a 1-4 start this year.

Carroll’s successful challenge Sunday night was one of many key twists that led to three Seattle touchdowns in a span of 1:53 of the third quarter.

Without those key moments, Seattle wouldn’t have been in position for Wilson’s electrifying 94-yard game-winning touchdown drive in the final two minutes.

And the kid-at-heart Carroll wouldn’t have been asked after the game why he prefers the heart-pounding comeback over an easy blowout.

“Because it is so much freakin’ fun,” he said. “We’re making memories.”

Mark Craig is an NFL and Vikings Insider. Twitter: @markcraigNFL. E-mail: