Romelu Lukaku is recovering from an ankle problem. (PA Wire)

Romelu Lukaku has posted a positive injury update after undergoing treatment on his ankle injury at a rehab centre in Belgium.

The Manchester United striker has been ruled out of Belgium’s World Cup qualifier against Bosnia-Herzegovina on Saturday, but manager Roberto Martinez admits the 24-year-old may play some part in Tuesday’s fixture at home to Cyprus.

Despite his ankle injury, Lukaku has not been sent back to United and is instead attending the Move to Cure clinic in Antwerp, which is run by Lieven Maesschalck, the head physio of Belgium’s national team.

Lukaku is now in a race to be fully fit for United’s trip to Liverpool after the international break on October 14.

Martinez is aware that risking Lukaku could anger Jose Mourinho and admits the striker will not play for Belgium, who have already qualified for the World Cup, unless he is fully fit.

‘Romelu would like to join in, but he must be fully recovered,’ said the former Everton boss.

Lukaku has scored seven Premier League goals for United this season. (AFP/Getty Images)

‘We will wait for as long as possible to make a decision and we also keep in touch with Manchester United.’

Lukaku has made an immediate impact at United after joining from Everton in the summer with 10 goals in all competitions so far.

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