London, United Kingdom: Arsenal manager Unai Emery has challenged troubled star Mesut Ozil to prove his worth after a season marred by injuries and illness.
Ozil has failed to repay Arsenal's decision to hand him a lucrative new contract last season that made him one of the Premier League's top earners.
The German midfielder has spent much of this term on the sidelines nursing a series of minor ailments, with Emery often leaving out Ozil on the rare occasions he is fully fit.
Former Arsenal manager Arsene Wenger, who signed Ozil from Real Madrid, this week questioned whether the club-record contract had left the player in the "comfort zone".
After reportedly expressing frustration at Ozil's lack of work-rate in the past, Emery admitted the 30-year-old has to train more consistently if he is to be selected in the future.
Ozil missed last week's Europa League last 32 first-leg defeat at BATE Borisov as he was still feeling the effects of a sickness bug.
He trained on Wednesday and could feature in the second leg against BATE on Thursday.
"First, mostly, the key is in his hand. And he is working very well this week. I ask him in our conversations to be consistent. To be available for us training," Emery told reporters.
"When you can train with regularity, consistency, you can help us after in the games. Now I think this week is good for all the players because we are in an important moment for the season.
"He needs to be consistent, be available for training, for the matches. Without the injuries, without being sick. Like that, I think we can see the best Mesut with us."
BATE stunned Arsenal last week by securing a 1-0 lead to defend at the Emirates Stadium, with the Belarusian champions having not played a competitive game since mid-December.
The Gunners remain favourites to advance given the gap in quality between the two sides.
But Emery is prepared for a tense evening and he called for loud backing from Arsenal fans as his team look to advance in a tournament that brings Champions League qualification for the winners.
"For us tomorrow is a very important match. After the first result we must manage the game and also know we may need more minutes after the 90 minutes," he said.
"It is also very important to play in our stadium with our supporters, and we need their support for this match and I hope there is a big atmosphere for us.
"Together, with their support, I know our players can play and give their all."