Kieran Tierney needs surgery on his dislocated right shoulder and is set to miss three months of football for Arsenal.

Arsenal confirmed on Saturday that Tierney will undergo surgery next week. They expect the rehabilitation period afterwards to take around three months.

It’s a big shame for the summer signing, who was only starting to get back to full match sharpness after another injury. Tierney is still only up to nine Arsenal starts at this point in mid-December.

The big question now is how Arsenal deal with the setback. Sead Kolasinac will start for the most part, but he can’t play every game for the next three months.

Tolaji Bola may be an option, as the 20-year-old is still waiting for his first-team debut. He’s mostly having a positive season with the u23s bar a couple of minor injuries and the odd off-game.

Bukayo Saka can play left wing-back or left-back, but it’s a waste of his talents to drop him so deep. He’s also not as solid defensively as some of the alternatives. He makes good recovery runs and tackles but can’t face an attacker up as easily.

Zech Medley is a centre-back who can also play on the left, so he’s also an option. Presumably, that’s why he was in the squad for the Liege trip on Thursday. He struggled in the position with the senior side in the mid-season friendly in Dubai earlier this year though.

Ainsley Maitland-Niles can play at left-back, and he did so last season. However, with Hector Bellerin’s injury problems, Maitland-Niles might be needed at right-back just as often.

There’s clearly no perfect solution, and Arsenal may have to look to the transfer market instead. A loan deal until the end of the season would work well if one is available. Whatever happens, we wish Tierney well with his recovery.