Robert Allenby's bizarre season took another strange turn when his caddie walked off midway through the first round of RBC Canadian Open on Thursday.

It is second time in eight years that Allenby's caddie has quit during the round, leaving the player to find a spectator to carry his bag for the remaining holes. The trouble started at Allenby's fourth hole, the par-five 13th at Glen Abbey, when the 44-year-old Australian and bagman Mick Middlemo disagreed over club selection for the approach shot.

His subsequent shot found the creek in front of the green, which led to a heated confrontation and a triple bogey. "My nerves have been rattled. I'm in shock," Allenby said after shooting 81 and withdrawing from the tournament. "This is the worst incident I've ever witnessed as a player. I said to him (Middlemo), 'You know this happens every week. We keep making bad mistakes and you're not helping me in these circumstances'."

Allenby is no stranger to such situations. At the 2007 BMW Open near Chicago, Matthew Tritton dumped the bag near the seventh tee, removed his bib and walked off. Two decades ago, another caddie quit on Allenby in the middle of the 1995 British Open at St Andrews.