U.S. Soccer filed a player tampering complaint with FIFA this week against Lyon owner Jean-Michel Aulas, SI.com has learned.

Over the weekend, Aulas tweeted at Portland Thorns player Allie Long about his desire for her to join Lyon. Portland owner Merritt Paulson went back hard at Aulas on Twitter about tampering with players under contract, and now U.S. Soccer has backed it up with a formal complaint.

Aulas also tweeted at Alex Morgan in the same way before he signed her to a short-term contract with Lyon this year. Morgan will play in the Women's Champions League final with Lyon vs. French power PSG on June 1 in Cardiff after ousting Carli Lloyd's Manchester City Women in the semifinals.

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Long, meanwhile, has emerged as a regular under U.S. manager Jill Ellis, playing both in the midfield and in defense. She started three times at the Olympics, the subsequent six games to close 2016 and four of the team's five matches in 2017.