Novak Djokovic
Djokovic has already suffered four losses in 2017 Getty

Novak Djokovic's year continues to be a lacklustre one as he crashes out of the Monte-Carlo Masters following a 6-2, 3-6, 7-5 quarter-final defeat to David Goffin.

The world number two was hoping to put his recent struggles behind him and win his second title of 2017, however, Goffin was able to upset Djokovic and defeat a top three opponent for the first time in his career.

Djokovic lost the first set 6-2 after an impressive showing from the Belgian but came back to level the scores, winning the second set 6-3.

The 29-year-old then looked like he would book a semi-final spot after going 4-2 up in the final set, however, Goffin rallied to comeback and eventually win 7-5 after taking his fifth match point.

"I started slowly probably because I played two long matches," Djokovic reacted, as quoted on TennisWorldUSA. "But I thought as the match progressed I was feeling okay. I was physically fine."

"We had a lot of exchanges, a lot of rallies. David is playing very quick. You know, he's a fast player. I thought I played very, very well for a set and a half, from the start of the second set.

"Then that unfortunate game when I dropped my serve, the match turned around. I had my chances, I definitely did. I just didn't use them."

The loss was already Djokovic's fourth of 2017, taking his record in the calendar year record to 14-4. The former world number one believes he is still improving though, compared to his previous performances.

"I'm doing everything that I can to play well," he added. "I think I'm playing better than I have in first couple months of the year. So that's a positive. But clay is very particular surface that requires, of course, a lot of practice, a lot of movement. Hopefully I'll get those in the weeks to come."

As for Goffin, the world number 13 will now face tournament favourite Rafael Nadal in the semi-final, with the Spaniard looking to become the first player in the open era to win the same tournament 10 times.

"It's the biggest test you can have on clay," Goffin said following the win. "He likes to play here. He won nine times. He likes to play on clay anyway. It's going to be very complicated. He runs all over the place. On clay, he can be a real wall.

"But I do have my own weapons. I have a good cross-court backhand. I can try to dictate the points, not let him play. I saw today that I could be even more aggressive than usual. I will need to repeat that if I want to win matches."

Goffin will meet Nadal in their semi-final clash on Saturday (22 April).