The bearded Paire said the key to his 6-4 3-6 4-6 7-6(6) 6-4 win was to throw caution to the wind, hit out, and most of all, have fun.
“The thing is you have to have pleasure on this match,” said Paire “You have to feel good on court, to have fun, you know. You’re going to play on big court, on big stadium.
“My coach told me the most important thing is when you go out of the court, you win, you lose, you don’t care, just have fun.”
Paire had lost his two prior matches against the fourth-seeded Nishikori, including a four-set, third-round clash at the 2013 French Open.
But last month, the 41st-ranked Paire raised his confidence by winning his first ATP Tour title at Bastad.
“When I come on court, I know I can beat Nishikori. I played him twice; I lost two times, but very tough matches,” he said.
“So when I come on the court, I say, ‘Come on. You can beat Kei.’
“So the most important thing is to feel good and to have fun. I think today that’s the most important thing.”
The victory was Paire’s third career top-10 win (3-16) and his first over a top-five opponent (1-8).
Playing with abandon, Paire fired in 21 aces to only three for Nishikori and belted 64 winners, 30 more than Nishikori.
Attacking so aggressively, the Frenchman also far outnumbered Nishikori with 67 unforced errors, 31 more than the first Japanese player ever to play in a grand slam final.
Paire survived a pair of match points at 6-4 in the fourth-set tiebreaker and got some help from Nishikori errors in winning the next four points to force a fifth set.
“To be honest, I think I’m lucky,” Paire said. “Today, for me, it’s a good day. I’m really happy to win.”
Paire next plays Marsel Ilhan of Turkey, who advanced when Czech Radek Stepanek retired while trailing 6-0 2-6 6-4 3-2.
(Editing by Mark Lamport-Stokes)