Kristoff wins, Boonen goes down badly in Paris-Nice opener

Boonen was moving along comfortably towards the rear of the peloton as the stage reached its conclusion, but he clipped the bike in front and fell very badly.

The Belgian was left in agony on the tarmac, clutching his arms in pain with what was quickly suspected as a broken collarbone - an injury that could end the former world champion's hopes of glory in the upcoming Spring Classics.

Kristoff won the bunch sprint ahead of FDJ's Nacer Bouhanni, with Bryan Coquard (Europcar) coming third.

Michal Kwiatkowski, winner of Sunday's time trial prologue, retained the yellow jersey ahead of Rohan Dennis and Tony Martin.

"I'm really happy. It's my first stage win in Paris-Nice and this is my fourth time coming here. It's a step-up for me," said Kristoff.

“I was sitting in good position but [John] Degenkolb went early and I wasn't sure if I would hold on until I crossed the line."

1. Alexander Kristoff (Nor) Team Katusha

2. Nacer Bouhanni (Fra) Cofidis, Solutions Credits

3. Bryan Coquard (Fra) Team Europcar

4. Heinrich Haussler (Aus) IAM Cycling

5. Giacomo Nizzolo (Ita) Trek Factory Racing

6. Jose Joaquin Rojas (Spa) Movistar Team

7. Moreno Hofland (Ned) Team LottoNL-Jumbo

8. Niccolo Bonifazio (Ita) Lampre-Merida

9. Ben Swift (GB) Team Sky

10. Michael Matthews (Aus) Orica GreenEdge