Mesut Ozil's Arsenal career started with a bang, but in recent weeks he appears to have taken his foot off the accelerator.
The Germany international, who joined the Gunners for a club record £42.4m from Real Madrid in the summer, has failed to score in his last eight matches, while he spurned the chance to end his goal drought against Marseille on Tuesday night after hitting a dreadful penalty kick.
It was a lazy effort from a player who, as we've all seen since 2010, possesses extraordinary ability. Arsene Wenger would have expected a lot more from perhaps the only player in his squad widely regarded as world class.
But Wenger also would have expected more from Ozil in a number of other matches this season - particularly in those that have taken place in more recent weeks.
Ozil has only found the back of the net in one Premier League match this season - he did, however, score twice during that game against Norwich City in October - while he has only contributed a paltry one assist in his last seven league appearances.
These numbers simply aren't good enough - not purely on the basis that he cost over £40m, but also because of his unquestionable ability.
Ozil has drifted in and out of matches too often recently - and we've yet to really see the former Real Madrid star take a game by the scruff of the neck and inspire the Gunners to victory.
He's more than capable, so why the lacklustre performances?
Is he struggling to motivate himself to play for Arsenal? While the north London outfit would be classed as Premier League heavyweights, they pale in the stature stakes when compared to European giants Real Madrid, where the pressure to perform is intense.
It could be argued that he was playing alongside better players in a less competitive league before joining Arsenal, but his current teammates are still top-class, so it's not as if he's on a different wavelength to the likes of Jack Wilshere and Santi Cazorla.
Ozil is capable of playing with more hunger and determination, as we saw after his missed penalty against Marseille on Tuesday.
The 25-year-old responded by setting up Wilshere's second of the match, while he was unlucky not to get himself on the scoresheet.
Arsenal fans want to see the same commitment and effort on a more consistent basis - and surely Wenger does, too.
Perhaps he is saving himself for the most important months of the season after the New Year. Not to mention, of course, the 2014 World Cup finals in Brazil.
But Arsenal need an instant return for their money; they need Ozil to help them end their nine-year trophy drought.
And that will only happen when he finally hits top gear.