Kieran Tierney is in line to make a surprise comeback in Arsenal's Europa League semi-final first-leg tie at Villarreal, while Pierre-Emerick Aubameyang and Alexandre Lacazette are also in contention.

Scottish left-back Tierney suffered ligament damage to his left knee in the 3-0 defeat at Liverpool on April 3 and was originally expected to miss between four and six weeks.

Such a timescale would have left Tierney facing the possibility of missing the remainder of the season, but Gunners boss Mikel Arteta provided a much more positive update ahead of Thursday's trip to Villarreal.

"He didn't need the surgery that we were afraid of," said Arteta.

"He's been working like a beast every single day. I don't know if he's going to make it tomorrow, but he certainly wants to be as close as possible."

Captain Aubameyang has not featured since April 8 and had been receiving treatment for malaria, but Arteta confirmed he and Lacazette (hamstring) are in line to feature.

David Luiz has been back in training following a knee issue having been out since March, meaning Arteta has potentially a fully fit squad to choose from.

But the Spaniard insists no risks are being taken in a huge match for Arsenal, for who the Europa League represents their best chance of qualifying for European football next term given they sit 10th in the Premier League.

"We do need them because we know that we have some players that are in contention and they are the ones that can make the difference in a big tie like this," he added.

"But the word risk, I don't like it. I want to put players on the pitch that can perform and feel secure they can perform. If it is a risk or we are going to take a gamble, I don't think it is the right game to do it."

The match against Villarreal sees Arsenal come up against former boss Unai Emery, a coach who won the Europa League three years running with Sevilla and led the Gunners to the 2019 final where they were beaten by Chelsea.

Emery was sacked in December of that year following a downturn in results, though Arteta had nothing but praise for his predecessor.

"I spoke with him before I took the Arsenal job, he was really helpful, very experienced and successful manager," he said.

"I think there is no doubt that he's got the tools and knowledge to manage at the top level."