Novak Djokovic is still to drop a set at the French Open after sweeping aside Italian qualifier Salvatore Caruso 6-3 6-3 6-2 to make the fourth round.

The Serb has never lost a Grand Slam match to a player ranked as low as world number 147 Caruso and breezed to victory in two hours and four minutes.

He is three wins away from the final and a possible meeting with 11-time champion Rafael Nadal.

Fifth seed Alexander Zverev withstood Dusan Lajovic's fightback to advance.

The German, who lost to Austria's Dominic Thiem in the last eight at Roland Garros last year, finally prevailed 6-4 6-2 4-6 1-6 6-2.

Serbian world number 35 Lajovic also took Zverev to five sets at Roland Garros last year.

Sixth seed Stefanos Tsitsipas also had to work hard, finally overcoming Filip Krajinovic 7-5 6-3 6-7 (5-7) 7-6 (8-6) in a match played over two days after bad light stopped play on Friday.

The Greek will play 2015 champion Stan Wawrinka in the fourth round after the Swiss beat Grigor Dimitrov, while Zverev will take on Fabio Fognini following the Italian's 7-6 (7-5) 6-4 4-6 6-1 win over Spanish 18th seed Roberto Bautista Agut.

Djokovic's serene progress into the second week continued as he lost just 19 points on his own serve in his victory over Caruso.

The 32-year-old, who is the Wimbledon, US and Australian Open champion, is bidding to become the first man in the Open era to hold all four Grand Slam titles simultaneously on two separate occasions.

Tsitsipas, who lost to Nadal in the Australian Open semi-finals in January, is another potential final opponent for 15-time Grand Slam champion Djokovic.

The 20-year-old beat Nadal in Madrid last month and won his first clay-court Tour title in Estoril.

His victory over Serbia's Krajinovic makes him the first Greek to reach this stage at Roland Garros since 1936.

Elsewhere, Argentine eighth seed Juan Martin del Potro made short work of Australian Jordan Thompson, racking up a 6-4 6-4 6-0 win in a minute more than two hours.

Last year's US Open runner-up will face Russian Karen Khachanov next after the 10th seed's 6-1 6-4 6-3 win over Martin Klizan.

Fourth seed Dominic Thiem once again needed four sets to beat his opponent. The Austrian, who beat Tommy Paul and Alexander Bublik with similar scorelines in the previous two rounds, overcame Uruguay's Pablo Cuevas 6-3 4-6 6-2 7-5 to book a meeting with home-crowd favourite Gael Monfils. The Frenchman was a 6-3 6-2 6-3 winner over compatriot Antoine Hoang.