Rafael Nadal beat David Goffin 6-3, 6-1 on Saturday in a controversial semi-final at the Monte Carlo Masters to put himself on the brink of a 10th title at the clay court showpiece.

The 30-year-old defending champion will face Spanish compatriot Albert Ramos-Vinolas, who defeated Lucas Pouille 6-3, 5-7, 6-1, in Sunday's final.

Nadal is also chasing his first ATP title since last April in Barcelona and the 70th of his career.

"It's tough to believe that I am again in a final here, it is unbelievable news for me," Nadal said. "It's another great event.

"I'm be able to start the clay court season playing a final in one of the most important events of the year. Personally, it's a very special place for me. It's something that makes me feel very happy. Very excited about it."

Nadal has beaten 29-year-old Ramos-Vinolas in their two previous clashes, both times on clay in Barcelona.

"He's playing better than ever, he's winning huge matches during the whole week," said Nadal of his next opponent.

"He's playing with big confidence, with great spirit of fight, overcoming tough situations in every match, and playing a high level of tennis all the time.

"I know that I need to be at my best to keep having chances, to fight for another title here. That's what I am looking for."

However, Saturday's semi-final turned on a controversial incident in the first set, when the chair umpire may have missed a ball mark and ended up awarding Nadal a point which denied Goffin a 4-2 lead in the opener.

The crowd turning against him, Nadal was the subject of whistles and jeers while the heart went out of Goffin who had made the semi-finals by seeing off world number two Novak Djokovic on Friday.

"When the umpire goes down and says the ball is good, what I can say? No, the ball is out?" Nadal said. "That's why there is an umpire there.

"If the ball is on my side, I see the ball is in, I give the ball to the other side? This (booing) for me is sometimes sad, especially in a place that I had a lot of success, in a place that I love. Sometimes that happens."

Ramos-Vinolas, the 15th seed who had knocked out number one Andy Murray and Marin Cilic, had never before even reached a Masters 1000 semi-final.

"To play Rafa, you never know. If he plays unbelievable, he's going to beat you," Ramos-Vinolas said.

"I have more confidence. It's impossible to negate that. Since Roland Garros (2016) maybe, I'm playing better. In South America (February) I did a final, two semi-finals, one quarter-final.

"The results are going better."

The Spaniard, who saved seven of nine break points, had come to the principality with only three previous victories from 29 matches against top 10 opponents.