A hamstring injury in the warm-up meant fellow full-back Hector Bellerin did not even start the game, while Granit Xhaka then suffered concussion and Nicolas Pepe a bruised knee.

The trio are all ruled out of the game against Liege and face a race against time to be fit for the Manchester City clash on Sunday.

Dani Ceballos and Rob Holding were already absent with hamstring and knee issues, respectively, and Ljungberg admits injuries are taking their toll on the shape of his squad.

"Of course, it's not good," he said. "We got one in the warm-up at West Ham, another full-back in the game. It's one of those freak things. one is to the head, another is the shoulder in a tackle.

"We can't do much about it, obviously it puts a strain on the squad but that's how it is."

Former Arsenal Under-23s manager Ljungberg has taken the likes of Zech Medley, Robbie Burton, Tyreece John-Jules and James Olayinka on the trip to Belgium while leaving big names such as captain Pierre-Emerick Aubameyang and Mesut Ozil at home.

Things would have to go catastrophically wrong for Arsenal to drop out of the Europa League, with Liege needing to win by a five-goal margin to overtake their visitors.

But Arsenal may need a win to secure top spot in Group F and therefore avoid what is likely to be a more challenging round-of-32 opponent.

At the age of 20 and with 34 first-team appearances to his name, Joe Willock will be an example for the young players called up by Ljungberg.

He too played under the Swede at youth level and was complimentary of the impact Ljungberg has already had on his burgeoning career.

"I worked with Freddie last year, in the Under-23s," said Willock.

"He taught me a lot, both on and off the pitch. He was like a mentor. I'm delighted he's in the job now. It's good for me. I just have to continue working hard and working with him."