Dre Greenlaw has always played like he has something to prove, and on Sunday in Seattle, that fire boiled over, but now the San Francisco 49ers will have to beat Washington without him.

The NFL handed Greenlaw a one-game suspension without pay on Monday after he headbutted Seahawks linebacker Ernest Jones IV, who had no helmet on, during San Francisco’s 32-29 win.

Greenlaw is expected to appeal, but the video evidence may not help his case. 

The sequence took only seconds as Sam Darnold scrambled toward the Seattle sideline and stepped out of bounds near midfield, and Greenlaw arrived a beat too late.

The flag for unnecessary roughness came immediately, and so did a wave of Seahawks defenders looking to stand up for their quarterback.

Jones got to Greenlaw first, and the two went face-to-face, with Jones appearing to push at Greenlaw’s facemask.

Greenlaw responded by driving his helmet into Jones’ bare head. Jones walked away bleeding. Greenlaw walked to the locker room.

The league’s officiating command center in New York tossed Greenlaw under a new rule that allows ejections after review, even without a flag on the field for the specific act.

The league later explained the suspension by citing its sportsmanship rule, noting that Greenlaw used his helmet against an unprotected opponent.

Unless his appeal succeeds, Greenlaw sits out next Monday night’s matchup with the Commanders and is cleared to return on October 20.

One of four hearing officers selected jointly by the league and players’ union, Derrick Brooks, Jordy Nelson, Ron Rivera, or James Thrash, will rule on the appeal.

That’s a meaningful absence. Greenlaw is second on the team with 37 tackles in his return to San Francisco after a one-year stop in Denver.

He’s the defense’s tone-setter between the tackles, and prime time on a short week is a tough spot to lose that.

The frustrating part for the 49ers is how familiar this feels. Sunday marked Greenlaw’s third career ejection and his second suspension.

He was thrown out of a 2022 game against the Chargers for a hit on Justin Herbert. A year later, in Philadelphia, he was ejected after his sideline run-in with Eagles security chief Dom DiSandro.

Last October in Denver, he earned a one-game ban for chasing down referee Brad Allen and threatening him after the Broncos’ wild comeback against the Giants.

Nobody in Santa Clara wants Greenlaw to play softer, considering his physical style is a big reason Kyle Shanahan’s defense brought him back.

Still, there’s a difference between edge and recklessness, and he keeps drifting across it in moments that hurt his team.

San Francisco survived it Sunday, holding on for a narrow division win. Against Washington, the 49ers will find out how much they miss him, and Greenlaw will have a week to think about what his temper is costing them.