Cameron Norrie extended the upset chaos at the ATP Montreal Masters on Thursday, saving a match point in defeating Alex de Minaur 5-7, 7-6 (7/5), 6-1.The battling British winner trailed a set and a double break against the Australian third seed, who folded in the final set of an epic lasting for almost three hours.De Minaur, who had been the highest remaining seed in a depleted draw, could have closed it out in straight sets with a match point chance in the eighth game of the second set.The tournament had already seen an early exit from top seed Alexander Zverev, an injury pullout from Canadian second seed Felix Auger-Aliassime and a loss by fourth seed Daniil Medvedev.The US Open tuneup hardcourt event had already been hit by the absences of world number one Jannik Sinner and 24-time Grand Slam singles champion Novak Djokovic.The result leaves fifth-seeded holder Ben Shelton as the new man to beat going into the fourth round.Norrie said he had to win a struggle."It was a great match to win and test my level," said the 2021 Masters champion at Indian Wells. "I can take so much confidence from this one."The level was so high in the first set. He came out firing and I had to match it. Alex stayed tough and stole the first set but took his foot off the gas just slightly in the second."I just battled point for point and managed to come out 6-1 in the third set. I was fortunate and I'll take (the win)."De Minaur, losing finalist in Canada three years ago to Sinner, seized a 4-1 first-set lead to take the opener, winning six of seven games.Norrie began turning the tide in the second set, levelling with a winning tiebreaker before running away in the third, taking match point 62 minutes after de Minaur blew his match point."I was in a good position," de Minaur said. "It's tennis. As we've seen, anything can happen. It's not the easiest of conditions out here."I gave myself chances early in the third set, and then I just played some bad points in a row and then got behind."It all just went very quickly."Norrie will next play Arthur Fils after the Frenchman defeated Mariano Navone 6-3, 6-2, staking his claim for a comeback effort after missing months of play from a year ago and extending to February.The 44th-ranked Argentine Navone lost his 22nd career match against a top-30 opponent. Fils advanced on his second match point, winning as he overcame 30 unforced errors with a solid serving performance that included four aces and four breaks of the Navone serve."I couldn't put in a serve during warm-up," the 24th-ranked winner said. "But I found my rhythm during the match and hit some good spots."'I enjoy being back'With no top five players left in the depleted draw, the path is opening for the survivors in French-speaking Canada."It has been a tough time for me, I was injured a lot," Fils said. "But I enjoy being back on the big stage - it means a lot."Jiri Lehecka, at eighth the highest seed remaining after Shelton, stayed alive with a 6-3, 6-4 win over Belgian Alexander Blockx.He will next face Spanish teen Rafael Jodar, the Washington runner-up who beat 13th seed Lorenzo Musetti 6-4, 6-3."I did a great job on returns and generally played very solid," Jodar said. "I'm super happy with the performance."