Robin van Persie has handed the Netherlands a fitness worry ahead of the World Cup after the Manchester United striker picked up a groin problem in Wednesday's 2-0 friendly win over Wales in

Van Persie appeared to be in pain and held his groin when he left the pitch at halftime and Dutch coach Louis van Gaal took no risks over the fitness of his star striker as the 30-year-old was immediately replaced by Jeremain Lens.

Now Van Gaal, whose 23-man squad fly out to Rio de Janiero on Thursday, will be praying that his captain is not ruled out for a significant period of time and can recover from the injury scare to participate in the Netherlands' World Cup opener against reigning champions Spain in Salvador on June 13.

Before his half-time departure, Van Persie set up Arjen Robben for the opening goal of the friendly in the 32nd minute at the Amsterdam Arena.

Robben then turned provider to allow substitute Lens to double the Dutch side's advantage by tapping home from closerange on 76 minutes.

Prior to kick-off, there was great colour and noise inside the national stadium to create a party atmosphere as the Dutch public waved farewell to their stars before the World Cup.

Manchester United manager in waiting Van Gaal had played a formation of 5-3-2 versus Ghana at the weekend, but the 62-year-old demonstrated his flexibility by changing his style to a 4-4-2 diamond against Chris Coleman's side.

Wales were without Gareth Bale, Aaron Ramsey and Ashley Williams while five of

Coleman's starting line-up had not played for a month since the Championship season ended and the hosts almost took advantage immediately.

Van Persie tested Wayne Hennessey's reflexes in the third minute with a low shot before Neil Taylor cleared the danger.

Robben then dragged a shot wide after Welsh debutant James Chester of Hull City was caught out by Stefan de Vrij's long pass.

Yet Chester and Wales gradually grew into the first period and almost took a surprise lead in the 20th minute.

Simon Church was released down the left flank and the Charlton striker's dangerous centre required a last-ditch clearance by Bruno Martins Indi.

The Dutch did not appear at their best, but that scare woke them up. Robben should have scored when the Bayern Munich wideman latched onto Wesley Sneijder's through ball and beat Hennessey only for Chester to clear off the line.

But that was a warning for Wales as Van Gaal's World Cup-bound side went ahead on 32 minutes albeit in fortunate circumstances.

Van Persie forced Hennessey into a low save with a fierce left-footed shot and the rebound bounced off Chester and into the path of Robben, who made no mistake as she slotted past Hennessey.

That settled the Dutch and skipper Van Persie came close to making it two just before the interval when he side-footed Daryl Janmaat's cross wide of the far post.

Then came the concerning sight for Oranje supporters as Van Persie clutched his groin when he left the pitch at the break.

But the Netherlands extended their lead courtesy of Lens, who side-footed home from close-range following a powerful and pacy burst by Robben to breeze past Danny Gabbidon as the Netherlands depart for Brazil in a positive frame of mind despite the concern over Van Persie.