Top seed Novak Djokovic's quest for a second career Grand Slam continued with another one-sided victory as he reached the French Open last 16.

The 2016 champion, aiming for a 19th Grand Slam, took six of nine break points and did not face one himself.

Djokovic's next opponent will be rising Italian teenager Lorenzo Musetti.

The Serb has played imperiously and intensely in his opening three matches, looking in prime condition after warming up for Roland Garros by winning a clay-court title in his hometown of Belgrade last week.

That came after he lost to Spanish world number three Rafael Nadal in the Italian Open final in his previous tournament.

"It was a different preparation, I had never done that but I chose to because the tournament was in Serbia and we had a free week where we were not obliged to be in a bubble," Djokovic told Eurosport.

"I had a fantastic tournament in Belgrade and played at the level I desired in Rome. Coming into Paris I felt I didn't spend too much energy, I actually felt I gained a lot of energy from Belgrade.

"So far it has proved to be a good call."

Djokovic agreed his display against Berankis was "almost flawless".

"I'm always my biggest critic and you can always do certain things better," he said.

"It couldn't be much better than this, especially the first and third sets. I served well, moved well and made him play."

Musetti, 19, is playing in the main draw of a Grand Slam for the first time and went through to the fourth round by beating compatriot Marco Cecchinato in an entertaining contest where the pair hit a combined 106 winners.

Two audacious winners from Musetti - a behind-the-back volley and a flicked lob after he scampered back to the baseline - were particularly special as he won 3-6 6-4 6-3 3-6 6-3 in his first five-setter.

Elsewhere, 10th seed Diego Schwartzman moved into the last 16 without having dropped a set this week.

The 28-year-old Argentine won 6-4 6-2 6-1 against German veteran Philipp Kohlschreiber as he looks to go even better than his appearance in the semi-finals last year.

Next up for him is Jan-Lennard Struff, another German, who knocked out talented Spanish teenager Carlos Alcaraz with a 6-4 7-6 (7-3) 6-2.

Italy's Jannik Sinner, another teenager tipped to become one of the world's leading players, is also through to the last 16 after winning 6-1 7-5 6-3 against Sweden's Mikail Ymer.