Mathieu van der Poel (Alpecin-Deceuninck) has vowed to continue racing the Tour de France, despite expressing disappointment about his state of fitness.
The Dutch superstar was rated as one of the pre-race favourites to win stage five that took in 11 Paris-Roubaix cobbled sectors.
But just as he was absent the day earlier when his long-time rival Wout van Aert attacked with 10km to go, Van der Poel struggled to keep pace with the leading group on the fifth stage, and he finished almost four minutes behind winner Simon Clarke.
Speaking to a collection of press afterwards, the 27-year-old sighed: "Instead of better, I was worse. I'm a shadow of myself right now and that's frustrating. I have no idea what causes this. I wish I knew."
The multi-disciplined rider finished fifth in the opening time trial in Copenhagen, but that result was a deception of his actual form, he claimed.
"I didn't feel well then, either," he added. "The two stages after that were easy, so it was not noticeable then. However, I already noticed that if I ride fast I was on the limit. Today I couldn't even move on the cobbles - I knew it would be difficult.
Asked if he would stick the race out in search of his better legs, he replied: "For sure. I hope I will find them, otherwise it's going to be a long Tour. I don't know what causes it."
Van der Poel made his Grand Tour debut last July when he memorably claimed yellow on the second day and kept hold of the jersey for the following six stages before abandoning to focus on the Olympics.
He completed this May's Giro d'Italia, winning one stage and featuring in many breakaways, and he admitted before the Tour got underway that he was unsure if the Giro had made him a better rider or not, saying that he hadn't yet felt any tangible benefits.
Put to him that the Giro may have been the reason behind his lacklustre performances, he said: "This is only my third Grand Tour and the Giro was good, but not excellent.
"The week before the Tour I started to ride better but at altitude in Livigno I didn't feel it, either. I haven't reached the level I want for a while."
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