The Wimbledon champion was allowed only six games as he was completely overwhelmed by an opponent who cut him down to size in brutal fashion to set up a final against Novak Djokovic.
Murray had no break points and scored only 10 points on the world number one's serve as the claycourt machine spat out forehand winner after forehand winner.
He has now lost 15 times to Nadal, winning only five.
"Today he was hitting extremely hard, extremely heavy, returning well, and was hitting it well on the run," a glum-looking Murray, the seventh seed, told reporters.
"Yeah, that's the toughest match I have played against him."
Murray's recent performance against Nadal in Rome where he pushed the eight-times French champion close offered hope that the Scot could cause a shock on Phillipe Chatrier court.
"I played a very good match against him in Rome. I played a tactically very good match against him in Rome," Murray said.
"But, again, you can go out there with all the tactics in the world, but when he's hitting the ball like that, it's very difficult to hit the ball where you want to."
Murray was not helped by the hot weather, which added some fizz, spin and bounce to Nadal's topspin shots.
"His shot was bouncing incredibly high. It was very difficult to do much with the ball," Murray, who won the first point of the match with a glorious backhand but was second best from then on, said.
"Then when I did have the opportunity, I wanted to make a winner or make him run too much, trying to hit too close to the lines, and ended up making a lot of mistakes."
Murray, who has been without a coach since he parted ways with Ivan Lendl in March, said having a new face in his corner would have made no difference.
"I don't really think that's down to coaching decision," he said. "A lot of it comes down to how well he plays."
Murray added that there was a "50-50' chance that he would hire a coach before Wimbledon.
He switches to grass next week at the Aegon Championships at London's Queen's Club where he is defending champion but said it would take him a few days to recover from the punishment dished out by Nadal on the Parisian clay.
"I probably would rather have a little bit of time after a match like that, to be honest," said Murray.
"I mean, it's been a good tournament for me in many respects, but I'm very disappointed with today and how that match ended.
"Ideally I would like a few days away to think about it and then start getting ready again."
Once he gets his feet on the green grass of home, however, Murray believes his energy levels will return after some gruelling battles in Paris.
"I'm really looking forward to going back," Murray, who beat Djokovic to become Britain's first Wimbledon men's singles champion for 77 years last July, said. "I think it will give me a lot of positive energy."
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