Marin Cilic says a series of painful defeats at the hands of Novak Djokovic equipped him to finally overcome the endangered world number one at the Paris Masters.
Cilic, the 2014 US Open champion, defeated his Serbian nemesis for the first time in 15 attempts on Friday, a run stretching back to their initial meeting in 2008.
The result could yet have significant consequences - if Andy Murray reaches the final of the ATP Masters-level event, he will depose Djokovic and become the first British world number one.
Djokovic ended Cilic's defence of the US Open at Flushing Meadows last year and has also beaten him twice at Wimbledon and once at the French Open since 2014.
It was finally time for revenge in the French capital, as a hard-fought 6-4 7-6 (7-2) victory ended the long hoodoo.
"We've had a lot of tough battles, tough matches in the last couple of years," Cilic said.
"It just helped me to prepare better. I think I was serving really good today. Maybe I was not serving too big on some occasions but I was really hitting the spots well today. That was helping me stay in the match, not giving him too many chances."
Cilic missed his first opportunity to seal the contest after taking a 6-5 lead in the second set, but dominated the following tie-break.
"In the end a few points are going to decide these kind of matches, I was just glad I kept my cool after Novak saved those two match points," he added.
"I was maybe not winning too many points on his serve but I felt I was close to [getting] some chances. And obviously 5-4 [down] in the second set, I broke him there.
"That gave me a good heads-up for the end of that second set. And you know, two match points, I didn't play too bad on them. I was hitting quite big ... I just kept focus and continued to play that way."
Cilic, who defeated fellow surprise finalist Kei Nishikori at Arthur Ashe Stadium two years ago to claim his only major to date, tactfully rejected the suggestion he is in career-best form, having mounted a late charge to qualify the ATP World Tour Finals at the O2 Arena.
"Maybe the best [form] of the season and [I'm] enjoying it," he said.
"The end of the year, it's so important to make it to London.
"London is waiting for me and then Davis Cup at home so a lot of tennis to go and I hope I can continue to play this well."
Cilic will face fellow giant John Isner, who overcame Jack Sock earlier on Friday, in a semi-final certain to be billed as the battle of the big servers.