Unai Emery insists Mesut Ozil needs rest despite playing just 71 minutes of football this season as the Arsenal head coach left the forward at home for the Europa League tie with Eintracht Frankfurt.
Ozil, 30, had not featured at all this season until he started Sunday's 2-2 Premier League draw at Watford.
He missed the start of the season after being the target of an attempted carjacking alongside team-mate Sead Kolasinac, while illness also saw him miss out.
Ozil regained his fitness but was still left on the sidelines until the weekend.
He retired from international football with Germany last year amid controversy and, on what would have been his first return to play in the country, he would have no doubt been in for a hostile reception from a fervent Frankfurt crowd.
But instead Emery offered up the rather bizarre excuse that Ozil was instead being rested alongside Sokratis Papastathopoulos - who has played every minute of the opening five Premier League games of the season.
"We are playing now a lot of matches and I want to use different players and also can have some rotation in the first 11 and in the 19 players in the squad for tomorrow and Sokratis and Mesut they rest this match," he said.
"I prefer after the Sunday match to rest that match and to train and to be ready for Sunday. Because we are going to play another match on Sunday. My decision is because he played and also I'm thinking tomorrow the focus and the first 11.
"After that I decided who are the players who can be the best for tomorrow and also the players not and that is Sokratis and Mesut.
There will now be plenty of attention on whether Ozil starts Sunday's league visit of Aston Villa, given he has been left out here.