Serbia s Novak Djokovic looks on as he plays against Peru s Juan Pablo Varillas during their men s singles match on day eight of the Roland-Garros Open tennis tournament at the Court Philippe-Chatrier in Paris on June 4, 2023. AFP
Third seed Djokovic and Alcaraz are on course to meet in the semi-finals at Roland Garros, where the Serb has yet to drop a set through three rounds despite struggling for his best form in the first week.
The 36-year-old said he is carrying several injury problems but is 16-0 in the fourth round in Paris.
"We don't have much time to start to name the many injuries I have, and the list is quite long," said Djokovic, who is attempting to reach the quarter-finals for a 14th straight year.
"I don't want to sit here and talk about these things that are not preventing me from playing. I still kept on playing."
Varillas, 27, is the first player from Peru to reach the second week of a Grand Slam since Jaime Yzaga made the US Open quarter-finals 29 years ago.
The world number 94 had never won a match at a Slam before reeling off three successive five-set victories at Roland Garros.
"When you enter the court the chances are 50-50, it's one against one," said Varillas. "I'll try to go and win."
Alcaraz is trying to return to the French Open last eight for the second year running.
He has looked every part the tournament favourite so far, but Musetti beat the Spaniard in their only previous meeting in the 2022 Hamburg final.
"I remember the match in Hamburg," said Alcaraz. "It was really, really tough. This is a match that I was really looking for, really want to play that match."
Musetti, the 17th seed, beat Djokovic en route to the Monte Carlo Masters quarter-finals earlier this year and is one of four men left yet to drop a set at the French Open.
Stefanos Tsitsipas takes on Austrian qualifier Sebastian Ofner in the last 16.
The Greek fifth seed, who a blew a two-set lead to Djokovic in the 2021 final, is into the second week for a fifth straight year.
- Pavlyuchenkova fights back -
Anastasia Pavlyuchenkova, the 2021 runner-up, became the first woman through to the quarter-finals after rallying from a set and a break down to dump out Belgian 28th seed Elise Mertens 3-6, 7-6 (7/3), 6-3.
The Russian, whose ranking has plunged to 333 after a serious knee injury, is the lowest-ranked women's Grand Slam quarter-finalist since the 2017 US Open.
Pavlyuchenkova will take on Karolina Muchova or lucky loser Elina Avanesyan for a place in the last four.
Australian Open champion Aryna Sabalenka plays 2018 finalist Sloane Stephens in the night session -- the first women's match to feature in the primetime slot this year at the seventh time of asking.
The French Open is the only major where Sabalenka, who has a chance this fortnight to overtake Iga Swiatek as world number one, has not reached the semi-finals.
Elina Svitolina has enjoyed a dream run in her first Grand Slam tournament since the 2022 Australian Open, following maternity leave and a break due to mental exhaustion after Russia's invasion of Ukraine.
She has refused to shake the hands of Russian opponents on the WTA Tour, but the former world number three has called her upcoming opponent Daria Kasatkina "brave" for being more outspoken regarding the conflict than her Russian compatriots.
"I'm thankful to Dasha for taking this position. That's what you expect from others, as well. It's really brave from her," said Svitolina.
Svitolina has won all six previous meetings and is eyeing a fourth French Open quarter-final against a player who made the last four in 2022.
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