Bennett, who also won Stages 1 and 2 of the event, continued his fine form in Belgium by emerging victorious by the narrowest of margins.
Bennett seals Binckbank hat-trick in close finish
Tour de France
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The Irishman produced a late burst in the final 10 metres and threw his bike to seal the win.
Groenewegen (Jumbo–Visma) came second, with Jasper Philipsen (UAE Team Emirates) third. Jurgen Roelandts (Movistar). The trio did well to avoid a crash on the final turn and fight it out for the podium places.
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The Bora-Hansgrohe rider sits top of the general classification, with Philipsen and Groenewegen both 20 seconds behind him.
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Volta ao Algarve
Bennett doubles up in Algarve, Hayter retains yellow jersey