The Dutchman built on his Amstel Gold Race in April when the Corendon-Circus rider pulled off an impressive victory.
Cummings had the lead with 250 metres to go, but was usurped by Van der Poel with a little over 100m remaining. His late surge suprised fellow sprinters Christophe Laporte, Andrea Pasqualon and Danny Van Poppel, who could not recover.
He pulled in and then away from Steve Cummings and the rest of the breakaway pack in a win that was suprising due to his recent lack of road racing. It was one of the few times he had been on a road bike in four months.
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The break has obviously helped him, as Van der Poel focused on his mountain biking and won three rounds at the cross-country World Cup.
The 24-year-old was nevertheless confident, saying: "I knew my shape was pretty good – otherwise you don't win a World Cup – but I'm still a bit surprised that I was feeling that good today."
He explained his tactics of starting a relatively late but long sprint compared to the usual dash in the last seconds.

Van der Poel: I timed my sprint to perfection

Van der Poel said: "Most sprinters' problem – and I often say this when I watch on television – is that they always wait a bit too long.
"Then they're surprised when someone starts sprinting sooner. Today, that was the case. You have to dare and launch the sprint from a little bit further out. If you wait until the last 150 metres to sprint, it's difficult to win.
"I know perfectly where I can launch my sprint until the end. I don't know why some sprinters are always waiting that long, because I think it's better to try to do your own sprint rather than waiting for someone else to launch their sprint. I think I rode a perfect sprint today."
The stage win means Van der Poel is now head of the general classification, but he is not aiming to retain the yellow jersey. With a 3.5km, 11.8 per cent climb to come on the third stage in Storheia, he expects others to leave him behind.
"Normally, it should be a little bit too hard for me. There are a few strong climbers here, I noticed today already – especially Lutsenko. He was really strong, so I think he's the favourite for the GC," he admitted.
"Of course I'm going to try to defend the jersey, but last year it was already too hard and this year the climbing is even harder."
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