The San Francisco 49ers got out to an early 10-0 lead, but they trailed 17-16 at halftime and were suddenly in trouble.

They needed a momentum swing against the Seattle Seahawks, and they got it.

They outscored the Seahawks 25-6 in the second half, and, after the game, head coach Kyle Shanahan pointed to what sparked the dominant second half.

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About five minutes into the third quarter, Deebo Samuel got the Niners in the red zone, but it appeared the Seahawks' Johnathan Abram rolled the receiver's ankle while making the tackle.

At the very least, Abrams picked up Samuel's leg and dragged him a few inches.

As Samuel asked for a flag, players had to be held back from one another. Samuel was slow to get up from the play.

Shanahan said the tackle "pissed the team off," and the Niners refused to take their foot off the gas pedal from there.

That drive ended in a Brock Purdy rushing touchdown. On the Seahawks' ensuing drive, the Niners recovered a Geno Smith fumble and turned that into another touchdown. The Niners scored on each of its possessions in the second half.

49ERS DOMINATE SEAHAWKS IN SECOND HALF TO ADVANCE IN NFL PLAYOFFS

Speaking to reporters after the game, Samuel said he stayed on the ground because, aside from the tackle hurting his ankle, he wanted to keep his composure and get his emotions in check.

Samuel got his revenge later in the game with a 74-yard touchdown in the fourth quarter to put the game out of reach.

"I don't know what he was trying to achieve by doing that, but it wasn't the smartest move, for sure," Niners linebacker Fred Warner added, referring to Abrams.

Samuel missed time earlier this season with an ankle injury, returning just last week.

The Niners won their 11th straight game and await their opponent for the divisional round.