According to his Alpecin-Fenix team, there is "no reason to question" the Dutchman's presence at the World Championships and Paris-Roubaix later this autumn, but the latest news is another blow to his end-of-season prospects.
It was first revealed that Van der Poel was struggling with a back injury a fortnight ago, when he had to return home early from a training camp in Italy. It has since been suggested the problem dates back to May and is linked with the change in position from the road bike in the spring to the mountain bike in the summer.
He first of all cancelled his plans to ride the Mountain Bike World Championships this weekend, and has now pulled out of the Benelux Tour, which starts on Monday and runs for seven stages. Van der Poel won the race last year when it was known as the BinckBank Tour, and the Classics-flavoured parcours this year makes it one of the key build-up races for Road Worlds hopefuls.
"Mathieu van der Poel was hoping to defend his title at the Benelux Tour, but unfortunately he will have to sit out the race. Due to his back problems, Van der Poel hasn't been able to train optimally in recent weeks and the Benelux Tour comes too soon," read a statement from his Alpecin-Fenix team.
"His adjusted training and race schedule for the coming months will be made according to his recovery. At this moment there is no reason to question participations at the World Championships and Paris-Roubaix."
The World Championships road race takes place between Antwerp and Leuven, with an undulating circuit in the south of Flanders, on September 26. Paris-Roubaix, which has been rescheduled from its spring slot, follows on October 3.
Van der Poel would ordinarily be considered a favourite for both events but his injury troubles now place a cloud of doubt above his status, if not his participation altogether.
As alternative preparation, he could opt to race the Tour of Britain, where he is also the defending champion, with the eight-stage race starting next Sunday on the final day of the Benelux Tour. The Tour of Luxembourg the following week could be the last chance to get a decent amount of racing in the legs, while there are a number of one-day events in the run-up to Worlds.
That depends on Van der Poel seeing improvements in his condition, as so far he has not been able to train with any intensity. According to a report in Wieleflits, Van der Poel is suffering from a herniated disc, with fluid between bones in his back.
The withdrawal from the Benelux Tour comes a day after his father publicly warned him against returning too early, and against riding Worlds and Roubaix if he's not at 100 per cent.
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