Bloemfontein - A controversial disallowed try helped the Crusaders beat Cheetahs 48-21 on Saturday and extend a winning run to nine matches since the Super Rugby season began.
The Cheetahs however believed they scored three minutes before half-time through winger Sergeal Petersen, only for the try to be disallowed because of a forward pass.
Television match official (TMO) Johan Greeff said there was "compelling evidence" that prop Ox Nche passed forward to Petersen, but TV replays suggested otherwise.
SuperSport TV analyst and former Springbok coach Nick Mallett was livid about a decision that occurred with the Cheetahs trailing 15-7.
"Where was the compelling evidence?" he asked. "It was a wonderful try that should not have been disallowed.
"Those watching will have seen a backward pass and not a forward one. I could say more about this but I won't."
Within two minutes, the record seven-time Super Rugby champions from New Zealand scored a try to lead 22-7 at half-time in Bloemfontein.
A possible one-point gap between the teams at the break had changed to 15 and the home players walked demoralised to the changing rooms.
The Cheetahs suffered a further blow when lock Armandt Koster was sin-binned four minutes into the second half for a ruck offence.
Tries were scored at regular intervals by the visitors thereafter and they finished with a bonus-point win and four-point lead in the New Zealand conference.
The unbeaten Crusaders have 41 points after 10 rounds, the Chiefs 37, title-holders the Hurricanes 33, the Highlanders 28 and the Blues 17.
As things stand, only the men from Auckland will fail to make the knockout phase of the competition.
It was the seventh loss in nine matches for the Cheetahs and their hopes of reaching the quarter-finals vanished some time ago.
South Africa will lose two of their six Super Rugby sides in a revamped competition next season and the Cheetahs and Southern Kings are expected to be axed.
Crusaders captain and lock Sam Whitelock attributed the winning streak this season to hard work on the training ground.
"That is where we lay the foundations for the victories," the All Black said. "Honing our skills in training makes it easier for us to perform on matchdays."
Fullback and man-of-the-match David Havili, who scored two tries, hailed the pack as the "unsung heroes" of the team from Christchurch.
"Full credit to our forwards for creating the platform," he said. "We are enjoying our rugby and there is something special about this group of guys."
Winger George Bridge (three), flyhalf Richie Mo'unga and substitute scrumhalf Mitchell Drummond were the other try scorers for the visitors.
Mo'unga missed only one kick at goal before being benched, slotting five conversions and a penalty.
Winger Raymond Rhule, Nche and Petersen scored tries for the Cheetahs and flyhalf Niel Marais kicked three conversions.