Novak Djokovic defeated an ailing Carlos Alcaraz 6-2, 5-7, 6-1, 6-1 on Friday to become the second oldest men's finalist in French Open history and close in on a record 23rd Grand Slam title.

Djokovic, a two-time Roland Garros champion, will break the record he shares with Rafael Nadal for the most men's Grand Slam titles if he beats Casper Ruud or Alexander Zverev in Sunday's final.

The 36-year-old Serb can also eclipse Nadal as the tournament's oldest winner and regain the number one ranking from Alcaraz, who was severely limited by cramp in the last two sets.

"First and foremost I have to say tough luck for Carlos, because at this level the last thing you want is cramp, physical problems at the last stages of Grand Slam," said Djokovic.

"I feel for him, I feel sorry and I hope he can recover."

Alcaraz's physical struggles drained the suspense as he gamely fought to carry on after a thrilling first two sets, with Djokovic dominating the opener before the Spaniard levelled in the second.

The 20-year-old pulled up clutching his right calf as Djokovic held serve for 1-1 in the third set, effectively giving his rival the next game rather than struggle through to the changeover.

Alcaraz was a shadow of the unshakeable, all-action player who began the match, his movement heavily restricted as Djokovic breezed through the rest of the set.

He returned for the fourth set after a bathroom break looking somewhat more mobile, but after Djokovic saved a break point in the opening game any lingering resistance from Alcaraz subsided.

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