Sparks flew and top jockeys Tye Angland and Olivier Doleuze all but came to blows in the weighing room at Sha Tin after a humble Class Three that turned into the race of the week, complete with the plunge of the season and a linked inquiry into tactics.

HK Racing Post reports: Richard Gibson-trained Winfull Patrol (Derek Leung Ka-chun) was sensationally-backed from $210 to $50 before he crossed to the lead from the outside draw then held on by a breath over Our Folks (Doleuze) to land the biggest successful touch of the term so far.

It was the third time Winfull Patrol had been smashed in betting this season, but ended more happily than his last run in October when he was ninth after severe interference.

"We were very worried after the last race, we thought he came back very lame and bruised and we thought had a bad injury. He very nearly fell and he was lucky he didn't," said Gibson. "It is great to have him back in good form."

"We knew he had the ability - he won down the straight in 55 something - but everyone had to show some patience and the reward was a big run today. It's nice to see Derek win one for us too, he does a lot of work for me in the mornings."

The plunge was all the more remarkable as Winfull Patrol shortened so dramatically even as John Size-trained Brave Brother (Angland) was also being hammered down from $50 to $30 and favouritism.

But the on-track action met its match in the aftermath that took place away from public eyes, as Doleuze and Angland faced off angrily in full view of the stewards over an incident in the early stages when Our Folks shaved Brave Brother in the first 100m of the race.

The Frenchman, drawn gate two, was trying to get across Angland in the rails draw to secure the box seat run, but cut it fine and checked Brave Brother and the two riders exchanged heated words on their way back to the jockeys' room after weighing in.

There was no escaping penalties for either, with $20,000 fines each for misconduct - Doleuze for making inappropriate contact with the Australian, and Angland for using inappropriate language to Doleuze - while Doleuze was also handed a 3-day careless riding ban with immediate effect.

Although it was Doleuze's first day back from a previous suspension, he had to take the new ban immediately to be back in time to ride Gold-Fun in the Stewards' Cup on January 19.