Mathieu van der Pol (Alpecin-Desseuninck) could only manage second place behind Wout van Aert (Jumbo Wisma) in the Zonhoven World Cup on Sunday afternoon.

Van der Pol missed most of last year's cyclocross season with a back injury, a problem that resurfaced at the midweek X2O Trofee in Koksijde.

On the sand course in Sonnhofen on Sunday, van der Pol caught up to van Aert early on, but a second crash on the third lap opened up a decisive gap.

From there, van der Pol rode to minimize the damage and held off Lawrence Sweck (Clerance Fristads) to take second place, 1:23 behind Van Aert.

In a flash post-race interview, "not good" was Van der Poel's succinct assessment. Not as good as I would have liked. My back is starting to hurt again and it's a little frustrating."

Van der Poel suggested that back pain played a role in his crashes in the sand.

"My back hurts and I have to focus 100% on the track and I can't do that. I can run a half lap or so at my own pace, but the pain is holding me back."

Van der Pol will travel to Spain on Monday for a road training camp with the Alpecin de Seuninck team. He will also race the following weekend in Hamme or Besançon before his duel with Van Aert at the World Championships in Vogelheide on February 5.

"Wout Van Aert is of course strong. But of course I have to be able to fight for longer," van der Pol told Sporza.

"Tomorrow I leave for a training camp in Spain. Here in Sonnhofen the public helped me, but now I don't enjoy racing cross."

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