"I need to improve to have a chance for the trophy at Roland Garros" - Novak Djokovic after losing to Aslan Karatsev in Serbia Open SF

Aslan Karatsev picked up the biggest win of his career on Saturday as he defeated World No. 1 Novak Djokovic in the semifinals of the Serbia Open. This is Djokovic's second surprise loss of the clay season; he had also fallen to Dan Evans in the third round of the Monte Carlo Masters.

Following the defeat, Novak Djokovic asserted that Roland Garros is his biggest goal during the European clay swing this summer. He did admit, however, that has to work on his game in the coming weeks if he hopes to contend for the trophy in Paris.

"Roland Garros still stays the main focus for me," Djokovic said. "(But) I need to improve, I need to play better. In order to have a chance for the trophy at Roland Garros I have to play much better than what I did today or (in) Monte Carlo. So yeah, there's much work ahead of me. And hopefully it can be beneficial for me when it matters most in Paris."

Novak Djokovic has been heavily involved in the organization of the Serbia Open, where his brother Djordje is the tournament director. Djokovic expressed hope of playing the second ATP 250 event that will be held in Belgrade next month, but reaffirmed that Roland Garros is where he wants to play his best.

"It was a good week, and a successful tournament in general for us," Djokovic added. "I'll hopefully play (here) in four or five weeks again, that's the plan. Let's see if that's going to happen. But Roland Garros is the goal, that's where I want to play my best."

It's the biggest win of Karatsev's career! 👏🇷🇺 @AsKaratsev outlasts Djokovic 7-5, 4-6, 6-4 after more than three hours on court in Belgrade. #SerbiaOpen2021 pic.twitter.com/aLrg4Uhu2t

— ATP Tour (@atptour) April 24, 2021

Novak Djokovic will now try and defend his titles at the Masters 1000 events in Madrid and Rome. Djokovic is in danger of losing his No. 1 ranking if he drops one too many points in the next few months; World No. 2 Daniil Medvedev is hot on his heels, and the Russian has a lot of points to gain in the coming weeks.

Dissapointed to lose at home, but it was an "awesome" performance from Aslan Karatsev: Novak Djokovic

Aslan Karatsev defeated Novak Djokovic 7-5 4-6 6-4 in Belgrade

Novak Djokovic staged a fine comeback to take the match to a decider against Aslan Karatsev, given that he was a set and a break down at one point. The Serb had plenty of chances to take control in the third set, but he squandered as many as 10 break points (and 23 in the entire match) to let Karatsev off the hook.

Djokovic expressed his disappointment at that, especially since he was playing in his hometown. The World No. 1 claimed he wasn't feeling "so great", and called the loss "painful".

"You never like losing at home, that's for sure," Novak Djokovic said. "It's painful, it's disappointing, I don't feel so great now. At the same time, I have to congratulate Karatsev who played very bravely. Awesome performance from him."

28 breakpoints is the most Djokovic ever produced in his 1140 career matches (ATP and Slams) https://t.co/omzaNTgldK

— enrico maria riva (@enricomariariva) April 24, 2021

Djokovic went on to shower rich praise on Karatsev, admitting that he was the "better player" when it mattered the most. The Serb also took some solace in the fact that he kept fighting despite his own struggles combined with the tremendously high level of his opponent.

"From my side, I played again on a quite low level. Just some flashes of some good quality tennis," Novak Djokovic said. "I was fighting, I mean that's a positive. I was trying all the way, the crowd was great, they tried to lift me up all the way till the end. Because of them, I think I won the second set. Unfortunately in the third he was just the better player - in the decisive moments. I had my chances, but, you know, that's sport."

For more updates on the Serbia Open, visit the tournament's official Instagram and Twitter handles.