Since assisting two of Arsenal's three goals in a 3-0 win away at Fulham on debut, the Brazilian has been less than impressive – and has played a full 90 minutes just once.
Indeed, in his eight games since thrashing Fulham, the summer signing has not added to his assist tally and is yet to score his first goal for the club.
Nicolas Pepe, a rival for the same position in the line up, has enjoyed a decent start to the campaign, having scored three and assisted two in the Premier League and Europa League so far – but Arteta has come out in support of the veteran forward.
Quoted by Goal, Arteta said: "He's getting better and better and we all know the quality that he has, and he's a great option to have on the pitch."
The Brazilian is also the club's second highest earner, reportedly on £220,000 a week, including bonuses. His recent form has left the Arsenal faithful debating his worth to the club and why Arteta continues to start him.
However, the Arsenal boss rebuffed the concerns, claiming: "He's a player who can make a difference, he's got the ability to find that last action to open the door when everything's really tight."
November hasn't got easy tests in store for the Gunners, however. They host Aston Villa on Sunday night, while away trips to Leeds and Molde are followed by a home tie against Wolves after the international break.
Source : 90min