Novak Djokovic is into the Paris Olympics quarterfinals. Russia's Daniil Medvedev loses

PARIS — Novak Djokovic is back in the Summer Games singles quarterfinals for the fourth time in five appearances at the Olympics. What he really wants, of course, is a gold medal, pretty much the only significant achievement missing from his remarkable resume.

Djokovic, a 37-year-old from Serbia who is the top-seeded man in Paris, needed a bit of time to assert himself Wednesday before taking control with a five-game run for a 7-5, 6-3 victory over Dominik Koepfer of Germany.

A top player on the other half of the men's bracket, 2021 U.S. Open champion Daniil Medvedev — a Russian who, like everyone from his country, must compete under the label ''Individual Neutral Athletes,'' identified by the French acronym AIN — exited with a 6-3, 7-6 (5) loss to Felix Auger-Aliassime of Canada.

Medvedev entered the day with a 7-0 head-to-head record against Auger-Alissime but is no fan of playing on clay: Five of his eight French Opens ended in the first round. Medvedev reached six Grand Slam finals, all on hard courts, with two of the five defeats at that stage coming against Djokovic.

Already the owner of a men's-record 24 Grand Slam titles and more weeks at No. 1 than anyone in the history of the computerized tennis rankings, Djokovic has proclaimed success at these Olympics his priority for the year. His one medal so far was a bronze in 2008 at Beijing after losing to rival Rafael Nadal in the semifinals; Djokovic also was beaten in the semifinals by the eventual champions at London in 2012 (Andy Murray) and at Tokyo three years ago (Alexander Zverev).

''The goal,'' Djokovic said, ''is to break that barrier of the semifinals.''

The real goal, of course, is gold.

Next up for Djokovic will be a familiar foe in a familiar setting: On Thursday, Djokovic meets Stefanos Tsitsipas of Greece for a spot in the final four. It's a rematch of the 2021 final at the French Open — which is contested each year at Roland Garros, the site being used for these Games — and Tsitsipas took the first two sets that day before Djokovic came back to win in five.

''The best thing that you can have as a tennis player is to have the memory of a goldfish, so that's what I've been trying to work on,'' said Tsitsipas, who beat Sebastian Baez of Argentina 7-5, 6-1 on Wednesday.

"I've actually erased it," said Tsitsipas, also the runner-up to Djokovic at the 2023 Australian Open.

Also moving into the quarterfinals was Carlos Alcaraz, the 21-year-old from Spain who won the French Open in June and Wimbledon 2 1/2 weeks ago to raise his Slam total to four, Tommy Paul of the U.S. and Lorenzo Musetti of Italy. Alcaraz and Paul will play each other in the quarterfinals, a rematch from Wimbledon, where Alcaraz won in the same round.

Against Koepfer, Djokovic was patchy in parts at the outset, not as crisp as when he got past Nadal in straight sets in the second round. This one was 5-all in the first set, with Koepfer ripping big forehands to manage to steer Djokovic along the baseline.

But he took the last two games of the first set, eliciting chants of his two-syllable nickname from the crowd: ''No-le! No-le!'' When Koepfer trudged to the sideline, he chucked his racket at his bench.

Djokovic then began the second set by going up 3-0. That's when Koepfer was visited by a trainer to get treatment for a blister on his left middle finger.

Koepfer is a 30-year-old left-hander who has a sub -.500 career record, only once made it as far as the fourth round at a Grand Slam tournament, is currently ranked No. 70 and never climbed higher than No. 49.

Djokovic was wearing a gray sleeve on his right knee, which was operated on in Paris in early June after he tore the meniscus during a French Open match. Surprisingly, he participated at Wimbledon less than a month after the operation and made it all the way to the final before losing to Alcaraz.

Now Djokovic is the first man to reach the singles quarterfinals four times at the Olympics since tennis returned to the Summer Games in 1988.