Arsenal have been rocked by a potentially serious injury to new signing Mikel Merino in his first training session.

The 28-year-old’s arrival from Real Sociedad in a deal worth north of £30m was confirmed on Tuesday, boosting Mikel Arteta’s central midfield options as the club allowed Fabio Vieira out on loan to join Portuguese giants Porto.

The Spaniard had been courted by the Gunners for some time, having starred for Spain during their triumphant Euro 2024 campaign earlier this summer, but he will have to wait for his debut after manager Mikel Arteta revealed that he’s suffered a suspected fractured shoulder after a training ground collision.

“It was very unfortunate,” Arteta told his Friday press conference. “Yesterday he had a collision and he has a shoulder injury, unfortunately. It looks like he is going to be out for a few weeks. [It was his] first session.

“He was really excited and everything was looking really good. He landed on the floor and Gabi [Gabriel Magalhaes] landed on top of him and it looks like he has a small fracture probably.”

On when Merino could potentially return, Arteta added: “We have to see. He was in so much pain. We’ll have to do some more tests on that and then we’ll have more conclusive answers.”

Arsenal’s treatment table already consists of defensive duo Kieran Tierney and Takehiro Tomiyasu, as well as Gabriel Jesus, who is struggling with a groin injury.

Those concerns haven’t stopped Arsenal from making a strong start to the new Premier League season. Victory over Wolverhampton Wanderers on the opening day of the season was followed up an impressive 2-0 win away at Aston Villa, courtesy of second-half goals from Leandro Trossard and Thomas Partey.

The three-time Premier League winners sit third in the table, trailing Manchester City and Brighton & Hove Albion on goal difference, and take on the latter in their final fixture before the first international break of the new season.

Arsenal have strengthened their squad with the signings of Merino, Riccardo Calafiori and goalkeeper David Raya on a permanent basis, and have allowed Aaron Ramsdale to join newly-promoted Southampton.

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