Sagan was a third of the way into his time trial when a woman and her dog casually strolled out onto the course across a zebra crossing, straight into the course of the road race world champion.
Thankfully for the dog walker, Sagan was able to take evasive action, nipping through a gap in the raised kerb separating the road from an adjoining bike bath, with other spectators out of the way.
His time trial ruined, an exasperated Sagan turned to shake his head at the woman before continuing with his ride.
After the stage, Sagan took to Twitter to say that while he's still a canine fan, dogs and bike riders don't combine well
This is far from the first time that a dog has got involved in a bike race, with Marcus Burghardt, Philippe Gilbert and Sandy Casar all having been brought down by dogs at the Tour de France in the past.
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