But I did try my best.
He conceded only two break opportunities to Djokovic, who converted one early in the second set.
"It was a game where I had to play well". It gives me the possibility to play another final and to continue in a positive line.
After a run of seven straight defeats in their rivalry, dating back to the 2014 French Open final, this can only be described as a statement victory.
Indeed, even with Djokovic opening serve, Nadal won the first four points for an immediate break, helped by a couple of uncharacteristic errors from the Serb.
For the third straight clay-court Masters 1000 event, Djokovic and Nadal have been drawn in the same half.
Romania's Simona Halep successfully defended her Madrid Open title in the Women's Tennis Association Premier Mandatory event.
"I knew I was playing well in the first set but I just couldn't take my chances". I could have played better today.
"To win 6-3, 6-1 against an opponent as good as Nick, isn't normal".
Djokovic hasn't reached a final since winning his first tournament of the year in Doha. But it was their first meeting since 2016 Rome and Djokovic is a much different player these days.
Again Djokovic's level improved as the set wore on to make Nadal serve it out. And again, that Rafa backhand was just nasty. The Spaniard put down his 24th victory, but Djokovic still has two more wins.
Djokovic was pleased with a productive week, but gave Nadal credit and also said, "I tried my best but it wasn't very high quality from my side". His quality was very high.
Djokovic had not been to the semi-final of a tournament since the Qatar Open in January and admits it has felt good to get back among the top players again. And the questions mount.
However, Murray cut a frustrated figure as he was swept aside by the 20-year-old Croatian for the second time in the pair's four meetings. "It was a positive week and a positive experience". He did get the better of me in most of the stats, most of the shots.
Twenty-year-old German Alexander Zverev continued his fine form with a 6-4, 6-4 win over 11th seed Tomas Berdych to set up a quarter-final against Pablo Cuevas, who beat Benoit Paire 7-5, 0-6, 6-1.
He told atpworldtour.com: " What's important to me is to make it to another final.
"He (Goffin) demands the most of you, he's one of the best in the world, one of the candidates to win the most important trophies".
Nadal was made to work harder in front of a partisan crowd in the second set as the reigning champion dug deep to defend his title with pride.
"It was an important match for me because it meant continuing with the good dynamic that I've been carrying for several months", Nadal said. "It shows you you're working in the right way", said Nadal, who has thrived after two years struggling with his game.
Nadal had been forced to withdraw in Paris with a wrist injury that decimated the rest of his season and saw him drop to No9 in the rankings at the end of the year.