In the battle between two former ATP Finals champions, Stefanos Tsitsipas won his first group match to keep his chances of progressing to the knockout stage of the Nitto sponsored, end-of-season extravaganza, alive.
It never seemed to kind of be ending for me. Even on the last game when he was serving, I still felt if I was able to put a few balls in, some opportunity might present, and it did Stefanos Tsitsipas
The Greek star beat the former world No.1 Daniil Medvedev 6-3 6-7(11) 7-6(1) after saving three match points in a long and exciting second set tie-break which he eventually won 13-11.
Medvedev’s loss means he will be unable to qualify for the semi-finals having now been beaten twice in the Red Group stage.
In the second match of the day, Novak Djokovic stormed past Andrey Rublev 6-4 6-1 to remain unbeaten and establish himself at the top of the Red Group plus a place in the last four but still has to face Medvedev in his last match.
The winner between Tsitsipas and Rublev will join Djokovic in the knockout stage to complete the group’s round-robin series and they will play that on Friday.
Wednesday’s clash between Tsitsipas and Medvedev is arguably the best match of the week as the Greek inflicted his second consecutive defeat over the Russian having taken early control of the encounter.
Tsitsipas broke for 2-0 in the opener which was all he required to then pocket the first set with a love hold.
Medvedev was stung into action in the second but while he pressed, Tsitsipas held on leaving a tie-break to settle the matter, in what turned out to be a thrilling clash in itself.
Medvedev took control early to lead 4-1 but Tsitsipas hit back to level and then serve-volleyed brilliantly to bring up match point which he failed to convert and then missed another chance after Medvedev had netted on a set point.
Medvedev saved a third match point after finishing off an incredible point with a smash from the baseline, and then won a 27-shot rally and managed to convert his fourth set point to force a deciding set.
After the drama of the tie-break, the third set went along more serenely on serve until Tsitsipas’ level dropped in the seventh game and Medvedev broke for a 4-3 lead.
Medvedev saved a break point in his next service game, but then produced a below-par game when he tried to serve out the match but was broken.
The tie-break was surprisingly one sided in comparison to the one played earlier with Tsitsipas seizing control by claiming the first six points in a row before allowing his opponent a point and then serving out after 2-hours and 21-minutes.
“It was very tiring out there,” said Tsitsipas whose record against Medvedev now stands at 3 won and 7 lost. “I’m so glad I overcame this, and I was able to enjoy it with the crowd. It’s a great win and I’m extremely proud of the way I thought. It never seemed to kind of be ending for me. Even on the last game when he was serving, I still felt if I was able to put a few balls in, some opportunity might present, and it did.
“It was great to get back into the match, I felt reborn, and what a great way to end it.”

Andrey Rublev couldn't contain his emotions
In contrast Djokovic required 67-minutes to dispatch Rublev, basically running away with the second set as the Russian was unable to find any answers to the rampant Serb’s game.
There were some close exchanges in the opening eight games but every time Rublev looked to be getting an edge, it was quickly snuffed out by the former five time champion.
In the 10th game, having had game point a couple when errors started to creep in at crucial points and frustration started to set in the Russian mind.
He slammed his racket into the court after sending a backhand wide to give Djokovic a set point which he converted with a beautifully struck backhand,
It was all Djokovic in the second set as a stunned Rublev’s frustrations continued to boil over to no avail.
“I played very, very well,” a more than satisfied Djokovic said following his win. “One of the best matches of the year without a doubt. He is a tough opponent. A great competitor. He possesses a lot of strengths in his game. I managed to find the right attitude and the right game.
“In the 10th game of the first set, I think he was 40-30 and we played a long rally and I just stayed in there and told myself chances will come. He went down in his energy a little in the second and I wanted to use the momentum and energy from my side in the first few games and it was a flawless second set.”
On Thursday debutants Taylor Fritz and Felix Auger-Aliassime meet for a spot in the semi-finals from the Green Group while in the dead match between Casper Ruud and Rafael Nadal – Ruud has already qualified while Nadal has been eliminated – the pair will be playing for ranking points and prize money.

Novak Djokovic serves during his round robin match against Andrey Rublev