The Germany international impressed in a 2-0 victory over Bayern Munich in the Champions League on Tuesday night after Ozil scored Arsenal’s second in added time at The Emirates.
The £42.5m club-record signing has scored two goals and has made five assists in his last five games in all competitions for the north London outfit.
However, former Republic of Ireland and United midfielder Giles believes there is still plenty of room for improvement for the World Cup winner.
Giles told Newstalk’s Off The Ball: “He played ok the other night. He scored a goal. He is a very talented invidiual as we know.
“He has to get the attitude that he is going to do it week in, week out. I don’t think he has that. You want to see that every week. But we don’t.
“He has to put the work rate in as well. Maybe last night will be the start of him doing that but I’d have my doubts.”
Ozil has scored two goals and made seven assists in 11 games in the Premier League and Champions League this season.
The Germany playmaker moved to Arsenal from La Liga giants Real Madrid in a club-record £42.5m deal in August 2013.
Arsenal will face Roberto Martinez’s Everton side at The Emirates in the Premier League on Saturday afternoon.
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