For the first time since his celebrated arrival last summer, Wayne Rooney will watch from the stands Tuesday when D.C. United hosts the Montreal Impact at Audi Field.

Rooney has remained healthy and effective in 24 appearances over two seasons, but after receiving a red card for a reckless tackle during Saturday’s ruinous performance against Los Angeles FC, he must serve an automatic one-game suspension.

MLS’s disciplinary committee could add an additional match, if it deems the act serious enough. Such a decision would rule him out of this weekend’s visit to Denver to face the Colorado Rapids. It’s unclear when the league will render a decision.

Meanwhile, United has had little time to prepare for a game without Rooney (four goals, three assists) and to recalibrate following the 4-0 home defeat to MLS’s front-runners, its worst performance since moving to Buzzard Point.

First and foremost for Coach Ben Olsen is deciding who will fill the front-line void. The natural option is Quincy Amarikwa, a veteran forward who was signed during training camp specifically to provide cover for Rooney.

However, Olsen could opt for Ulises Segura, a natural midfielder whom United tested at striker in preseason.

Olsen also threw out the idea of moving central midfielder Luciano Acosta into a higher role.

“A bunch of crazy options for me,” Olsen said Monday.

Regardless of who starts, United (3-1-1) is going to need additional production after getting shut out for the second time. Upon Rooney’s arrival last year, Acosta thrived. Tuesday’s game will require the Argentine playmaker to take greater initiative.

“Throughout the course of a season, we are going to have injuries and suspensions, and everybody has to stay in it,” Olsen said. “We had the luxury for a while of not living in that world, and we took advantage of it. And so now we have to take advantage of these games where our depth is being tested.”

The depth was first tested Saturday as Chris McCann replaced left back Joseph Mora, who is recovering from a broken jaw suffered the previous weekend at Orlando. McCann did not fare well against ruthless LAFC.

Montreal (2-2-1) will arrive in Washington with two conspicuous absences: Ignacio Piatti (66 goals, 33 assists since 2015) and Maxi Urruti (29 goals, 20 assists in 2016-18 for FC Dallas). Piatti is recovering from a knee injury, and Urruti is serving a red-card suspension.

In assessing his front-line options, Olsen sees Amarikwa, 31, as a hard-working player who accepts his reserve role. He holds the ball well and, Olsen added, “is a pain in the a-- to play against.”

His production, however, has been modest: 10 goals and 10 assists since 2015, though a major knee injury sidelined him for an extended period.

Segura is perhaps United’s best all-around athlete and has the ability to stretch back lines with his speed. He has appeared in all five matches as a sub.

Besides lineup decisions, Olsen has had to address the lackluster effort that resulted in a three-goal deficit after 32 minutes Saturday.

Playing again so soon, he said, should help the group recover.

“You’re not excited about any quick turnaround, but now that we got punched in the face, I am very happy — and I think our team is very happy — we don’t have to sit on that all week,” he said, “and we get to go out and hopefully prove it was an one-off and have a response to what was not a great game.”

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