Mathieu van der Poel's Classics campaign is now in doubt after he was caught in a huge crash during Nokere Koerse 2019.
The cyclocross world champion had been visible at the front for much of the cobbled one-day race in Belgium.
But the Dutchman was involved in a heavy fall in the final, being taken off the course by ambulance.
Van der Poel, 24, drove the pace for much of the 199.5km race around East Flanders, but was unable to cause any splits.
The race stayed together to set up a bunch sprint on the 300m cobbled, slightly uphill run to the line.
As the peloton hit the cobbled sector, Sunweb sprinter Max Walscheid fell near the front of the bunch.
Van der Poel was caught in the crash, rolling along the cobbles before being hit by a CCC Team rider.
He stayed on the floor and was then taken away by ambulance, as Walscheid walked to the line with his wrecked bike.
The race was won by Walcheid’s lead-out man Cees Bol, who opened his sprint late to beat Bora-Hansgrohe’s Pascal Ackermann.
Dutchman Bol was perfectly positioned to lead out team-mate Walscheid.
Bora-Hansgrohe’s Pascal Ackermann was first to open his sprint, but as he faded on the cobbled run to the line Bol was strong enough to pass him to take the win.
Bol’s victory is the first of 2019 for Sunweb.
Van der Poel was due to make his cobbled Classic debut this season, with his Correndon-Circus team being invited to a number of WorldTour one-day races.
He was expected to ride Gent-Wevelgem later this month, followed by Dwars door Vlaanderen, the Tour of Flanders and Amstel Gold Race.
While there are currently no details of his injuries, the crash may have jeopardised his plans.
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