Wayne Rooney has 11 goals and seven assists in 23 appearances this season. (Darren Staples/AFP/Getty Images)

In what was supposed to be his first appearance since announcing he will leave D.C. United after this season, Wayne Rooney will not play Sunday night against the Los Angeles Galaxy because of what team officials said was an upper respiratory ailment.

It ruined a highly anticipated showdown at Audi Field with Galaxy superstar Zlatan Ibrahimovic, Rooney’s former Manchester United teammate. Quincy Amarikwa started for Rooney, who this winter will join English second-tier Derby County as a player-assistant coach.

Transatlantic travel might have caused the illness. He flew to and from England during this past week.

Rooney leads D.C. in goals (11) and assists (seven). Before Sunday, he had played in all but two matches since arriving last summer (red card and minor injuries).

Meantime, United should learn Wednesday whether it has a realistic chance of replacing Rooney next season with Arsenal midfielder Mesut Özil, one of the sport’s highest-paid players.

Officials are scheduled to meet in Washington with agent Erkut Sogut to discuss a possible move this winter for the German playmaker, who might seek new horizons after six seasons with the London-based Premier League club.

The Washington Post reported news of United’s interest in Özil last week.

Özil, a member of Germany’s World Cup championship squad in 2014, was held out of Arsenal’s season opener Sunday at Newcastle for safety reasons. He and teammate Sead Kolasinac were victims of an attempted carjacking this summer, and this week another incident occurred outside Özil’s home.

Özil, 30, is under contract with Arsenal through the 2020-21 season and his earnings exceed $20 million annually, well beyond United’s wildest capacity. However, should Özil want to leave England, a creative financial arrangement could come into play.

One source close to the team said D.C. also had a discussion last week with former Liverpool forward Daniel Sturridge, who is a free agent and available to sign until the MLS roster freeze Aug. 30. However, his wage demands were too steep for the club.

In other D.C. news, newly acquired forward Ola Kamara was not cleared in time to play Sunday. He is in Toronto awaiting a work visa. Kamara used to have a green card for permanent residency, which would have allowed him to play soon after signing with United last week.

However, he apparently forfeited the green card last winter when he signed to play for Chinese club Shenzhen. No other details were immediately available. He seems likely to make his debut Saturday at Vancouver.

On another front, multiple people close to the team said European interest in Argentine playmaker Luciano Acosta has plummeted, leaving his best options for a new club to be in the Middle East. Acosta’s contact expires after this season, and he has declined United’s offers since last winter, when a potential transfer to Paris Saint-Germain fell through.

Acosta was benched Sunday, leaving the playmaking role to Paul Arriola, a natural winger.

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