Riders at the front of the peloton early in Saturday's Olympic road race encountered an unexpected obstacle.
A large black dog on an apparent kamikaze mission ran across the road and back as the main field zoomed through Twickenham, forcing surprised riders to swerve or brake to narrowly avoid a crash.
The near-disaster was reminiscent of an incident during Stage 18 of the Tour de France last week when a runaway dog on the course knocked Belgium's Philippe Gilbert and several others off their bikes. Gilbert was so livid that the carelessness of the pet's owner could have led to an injury preventing him competing in the Olympics that he nearly confronted the spectator before BMC team director John Lelangue intervened.
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Even though the appearance of another rogue dog eight days later at the Olympics drew some chuckles from spectators, rest assured the cyclists themselves probably weren't as amused.
Why would a fan bring a large dog with no leash to a cycling road race? You might as well let a pet parrot fly free during the air rifle shooting final or toss a great white shark into the swimming pool during the 200-meter breast stroke.