West Ham United co-chairman David Gold believes the club need to see Manuel Lanzini in action over the whole season before deciding whether to activate the purchase option in his loan deal.
The 22-year-old is on loan at the Hammers from Al Jazira Club for the season and has forced his way into manager Slaven Bilic's team.
Lanzini has impressed and is quickly becoming a fan favourite, leading to calls for West Ham not to wait and to agree to his permanent signing now.
But while Gold is also a fully paid up member of the Lanzini fan club, he believes the Argentine needs to be seen in action over an entire campaign, challenging the midfielder to show consistency.
"I know he is nicknamed 'The Jewell' and to say he is a gem is very appropriate at the moment!" Gold wrote on the club's official site.
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"He has incredible skills, but has a lot more to his game as well. He can tackle, pass the ball and has already shown that he can score goals.
"We have an option on him at the end of the season and you need to see him over the whole year and see someone perform at this level on a consistent basis", the co-chairman continued.
"But if he keeps putting in the displays that we are seeing at the moment, then the manager will keep picking him."
Lanzini will be looking to build upon his performances for West Ham after the international break when the Hammers are next in action against Crystal Palace at Selhurst Park.
Bilic's men currently sit sixth in the Premier League.
