Pierre-Emerick Aubameyang is available to start for Arsenal in their Europa League quarter-final against Napoli, says Unai Emery.

Illness restricted Aubameyang to a place on the bench for Sunday's 1-0 Premier League defeat at Everton.

Aubameyang came on as a half-time substitute as the Gunners' poor away form continued, but he could return to the side for the first leg against Napoli at Emirates Stadium.

"He had a small problem, he has been taking antibiotics for his sickness," Emery told reporters on Wednesday. "For tomorrow he's getting better and can start."

On Laurent Koscielny and Granit Xhaka, who are recovering from foot and groin injuries respectively, Emery added: "We are going to decide tomorrow."

Mesut Ozil drew attention for appearing to throw a coat in the direction of Emery after being substituted against Everton, but the Spaniard opted not to address the issue directly.

"Our focus is the match, taking confidence and being together, being calm when bad results come," Emery said when asked about the playmaker.

"We are on a good way but each match now is going to be very important. We are with our target, we know it is going to be very difficult. The best thing for us is to be together and strong, calm and with clear focus."

Napoli are arguably the toughest team Arsenal could have faced in the last eight but Emery is relishing the chance to test his mettle against Carlo Ancelotti.

"I think it's 50-50. Napoli have a big history like us, they're second in the table," Emery said of the Serie A side. 

"They're playing very well, they came from a strong group in the Champions League. They were very competitive. It's going to be difficult for us but we have confidence. We need to be very consistent in two matches.

"I have a great respect for every coach. Ancelotti is top. His career is amazing. For me, my challenge is every day and every year. All I did in my past is only for taking experience. I need to make a new future.

"This match is a big match at the level we want to play. It's a big test for us. We want to play against the best teams, Napoli are one of them.

"We need to be consistent each match. Each match gives a lot of information. Our balance is getting better but isn't enough. We need to win tomorrow. If we won't concede chances to score it's important.

"They have good performances in the season. We need to be very, very competitive in 90 minutes. Our idea is to win and not concede goals. We are prepared for extra time or penalties. It's going to be a very, very good game tomorrow."