Arsenal boss Mikel Arteta has revealed the club still don't know how long Lucas Torreira will be out for after the diminutive Uruguayan sustained a fractured ankle during the FA Cup victory over Portsmouth this week. 

The injury was sustained after the former Sampdoria defensive pivot had to be carried off on a stretcher after just 13 minutes following a challenge by Pompey defender James Bolton.

Arteta was positive but conceded the club still don't know the extent of the 24-year-old's injury, admitting it is too early to say how long Torreira will be absent for.

“He was quite positive this morning,” Arteta said. “I spoke with him and he was in pain. We don't really know exactly the extent of the injury. He needs to see the specialist tomorrow here in London and we will know more about it.

“For sure since I joined, the amount of things that happened [fitness wise] is enormous, but we just have to try to adapt," he added. "It's part of football. It doesn't only happen to us, unfortunately, it also happens to many other teams. So we cannot be crying about that. It is what it is.

“Sometimes it's bad luck, sometimes it's part of the game we play and sometimes things that we can avoid and do better as well but it is what it is.”     

Arteta previews Arsenal vs West Ham

Arsenal sit in tenth place in the Premier League, but incredibly, given their poor start to the first half of the season, they are only five points off a possible Champions League spot.

With Manchester City handed a two-year ban pending an appeal by the Etihad outfit, fifth place in the table could be enough to seal a coveted spot at Europe's top competition next season.

Manchester United occupy fifth but a win over the Irons at the weekend could boost the Gunners hopes considerably. 

"They caused a lot of problems to big teams recently," explained Arteta, previewing Saturday's derby.

"I know David [Moyes] because I worked with him for seven years. I know his structure, I know how organised he is. I am sure he'll put a team out there that is going to make life very difficult for us.

"They will compete, they will be physical. We need to use our resources, play our game and then just think about performing. That performance will bring the points home."

Arteta praises managerial counterpart Moyes

The Gunners return to league action against the East Londoners after two successive cup matches which resulted in a mixed bag. 

While Arteta's side suffered an unexpected Europa League knock out at the hands of 44-times Greek champions Olympiacos at the Emirates last week, they progressed to the quarter-finals of the FA Cup following a hard-fought 2-0 victory over Portsmouth at Fratton Park on Monday. 

Looking ahead to hosting West Ham at the Emirates, Arteta was quick to praise his managerial counterpart, Moyes, saying: "The thing that I admire the person, who he is, his values, how he deals with people, who he is, how he treats people, how he treated the players when they were there.

"How well he deals with creating a culture around a club, a chemistry between the players and a belief that we could do something as a team.

"And then he works really hard. He is extremely demanding, he's got character, Scottish character that is impulsive and I really enjoyed my time playing under him.

"I think he had a lot, obviously the Manchester United situation, I think what happened there was very harsh on him. I know how he is as a manager and my opinion hasn’t changed at all."

Aubameyang contract update

Arteta was also asked about club captain Pierre-Emerick Aubameyang, who has fewer than 18 months remaining on his contract. 

The 30-year-old striker has yet to sign a new deal at the club and speculation is rising the Gabon international will depart the Emirates this summer, with Barcelona monitoring the situation. 

However, Arteta insisted the club will speak with the star striker, explaining: "We will have to do that at some stage before the end of the season for sure and we will see the intentions that we have.

"Where we are sitting in that moment. I think it is difficult to predict that context right now. For me it is very easy. I want to keep him under any circumstances."

Injury updates

The club are hopeful January loan signing Cedric Soares will return to full training next week after recovering from a knee injury.

Sead Kolasinac is set to resume training by the end of March after a shoulder problem which saw him injured against Everton during the victory over Everton at the Emirates last month. 

Left-back Kieran Tierney is back in full training after recovering from a dislocated shoulder picked up against West Ham in the reverse fixture at the London Stadium during the Gunners 3-1 victory in early December. 

Arteta was hopeful the Scottish international will be able to compete for a place in the starting XI soon.

Injuries have limited the former Celtic defender to only 11 appearances for the Gunners since signing for £25m from the Glasgow giants last summer.