Arsenal manager Mikel Arteta began his pre-Brighton press conference with the disappointing news that Mikel Merino suffered an injury in his first training session with the team this week.

The new recruit sustained a shoulder problem and is expected to be out of action for a few weeks. “It’s very unfortunate,” Arteta said. “Yesterday he had a collision and got a shoulder injury. He’s going to be out for a few weeks.“It’s really bad luck and we were all very excited.

“He was looking very good, he landed on the floor, Gabi went on top of him and it looks like he’s got a small fracture probably. He was in so much pain, so we have to wait and see with the staff to do some more tests to have more conclusive answers.”

Arteta was asked for the latest updates on the availability of Gabriel Jesus and Takehiro Tomiyasu, who have been recovering from groin and knee injuries respectively, but are not in contention for Saturday’s game.

“[Gabriel] is progressing really well,” he said. “He had a muscle injury and is doing quite a lot of the stuff already so we expect him to be with us pretty soon.

“[With Tomi] at the moment it is difficult to say. It’s a bit slow, the process of the first phase of that injury. It’s probably for the medical team to say more than that. He’s not done any training yet.”