Arsene Wenger insists Danny Welbeck did not suffer a recurrence of his recent injury despite coming off at half-time as Arsenal lost to Cologne.
The Gunners, who made 11 changes from Saturday's north London derby success over Tottenham, were beaten 1-0 in their Europa League contest at the RheinEnergieStadion.
A controversial second-half penalty settled the tie as Mathieu Debuchy was adjudged to have fouled Sehrou Guirassy in the area when there was minimal contact.
Guirassy stepped up to convert the resulting spot-kick and give Cologne the three points which keeps them in the hunt to go through with Arsenal.
Wenger's side still progress as Group H winners despite the defeat and there was more good news for Arsenal fans as the Frenchman revealed the plan was always to withdraw Welbeck, playing his first game in a month following a groin injury, at the interval.
"It was planned before the game that he would only play 45 minutes," Wenger said.
"He has only just come back from injury, and we have three more games on Sunday, Wednesday and Saturday again."
Welbeck was on the bench for last weekend's Premier League clash with Tottenham but was drafted in for the European tie for his first start since October 14, and Wenger admits he did not want to chance the forward's long-term fitness.
"Medically, the risk was a bit too high to play him for longer because he has been out for a while. He has no problem," added Wenger.
"Of course, he was ready to stay on and frustrated to come off, but he's in good shape."
Arsenal next travel to Burnley in the Premier League on Sunday in search of their second away win of the season.