The Serb saw off Taylor Fritz in the last four at the ATP Finals on Saturday

Novak Djokovic's pursuit of a record-equaling sixth title at the ATP Finals continues after he edged out Taylor Fritz in their semifinal in Turin.

After coming through a mammoth three-hour, three-set battle with Daniil Medvedev in his final group-stage match on Friday, Djokovic returned to court less than 24 hours later at the Pala Alpitour to meet the better-rested Fritz.

It was a match settled by tight margins as the duo shared breaks of serve in each set before Djokovic got the better of the American in a pair of tie-breaks, winning 7-6 (7-5) 7-6 (8-6). 

Fritz had been serving for the second set at 5-4 ahead before Djokovic broke back and prevailed in the tie-break.   

The win for the Serb extended his perfect head-to-head record against Fritz to six wins from six in their career meetings. 

"I managed to crack his serve at 5-4. He was serving for the set, like Medvedev was serving for the match yesterday, and in those moments I guess I find another gear and manage to hold my nerve," Djokovic said of his gutsy win.

Djokovic, 35, came through the group stage in Turin with three wins from three, and should he clinch the title on Sunday, he would stand to pocket almost $4.75 million as an unbeaten champion.

Djokovic would also equal Roger Federer's record haul of six titles at the ATP Finals. The last of Djokovic's five successes at the event came back in 2015, when the tournament was being played in London.

Djokovic will next meet the winner of Saturday's second semifinal between Russia's Andrey Rublev - who was beaten by the Serb in the round-robin stage - and Norway's Casper Ruud, who came through his group with two wins from three matches.

Rublev, 25, and the 23-year-old Ruud are both targeting a first appearance in the title match at the ATP Finals.