TURIN, Italy-- Spain's Carlos Alcaraz made light of feeling under the weather as he dispatched Russia's Andrey Rublev in impressive fashion to revive his ATP Finals hopes on Wednesday.
The Spanish four-times Grand Slam champion has been suffering with respiratory issues in Turin and wore pink nasal tape against Rublev in a resounding 6-3 7-6(8) victory.
In the late match in the John Newcombe group, two-times former champion Alexander Zverev, the world number two, underlined his superb late-season form to beat Norway's Casper Ruud 7-6(3) 6-3 for his second victory of the week.
None of the eight men's singles matches so far at this year's season-ender have gone to three sets.
Third seed Alcaraz, bidding to win the title for the first time, looked far sharper than during his opening group match which ended in a straight-sets defeat by Ruud.
"I did surprise myself," Alcaraz, who had to abandon a practice session on Tuesday, said on court. "I just tried to focus on my game and what I had to do and not that I wasn't feeling well. Once you step on court you have to forget that.
"I felt good from the baseline running and felt I had more options today."
After sharing the opening six games, Alcaraz broke Rublev's serve with a scorching forehand winner and reeled off five successive games to seize control of the match.
World number eight Rublev, who also lost his opening match to Zverev, stayed with Alcaraz in the second set and could have earned a couple of break points at 2-2 had he not missed a routine ball after chasing a drop shot.
Both players served well to take the match into a high-octane tiebreak in which Alcaraz forged ahead but had to fend off two set points before sealing victory.
Rublev has now lost six successive matches at the ATP Finals in straight sets since reaching the semi-finals in 2022.
Nothing is decided in the group with even Rublev not out of contention but Alcaraz is likely to need to beat world number two Zverev in his last group match on Friday to qualify.
Should Germany's Zverev beat Alcaraz to win the group and Rublev defeats Ruud, three players would end up with one victory meaning sets and games would come into play to separate them.
The way Zverev is playing he will take some stopping. He was pushed hard by Ruud but turned up the heat in the first-set tiebreak, banging down a couple of aces to consolidate a mini-break on the way to taking the opener.
Ruud, who reached the final in 2022, could hardly have served any better, missing only nine first serves all match.
But a couple of errors when he served at 3-4 in the second set proved costly as Zverev got the decisive break.
Zverev then finished it off to chalk up his Tour-leading 68th match win of the year.
"I'm hitting my spots well (on serve) and the speed is maybe a bit up on last week," Zverev told Sky Sports.
"Today's match was better than the first match from the baseline."
The 27-year-old Zverev will now set his sights on Alcaraz, to whom he lost in the French Open final this year, although he did beat him at the Australian Open.
"We've played some very tough battles in Grand Slams this year, so I'm expecting a tough match. I'm looking forward to it and hopefully it will be fun to watch."
The Ilie Nastase group will be decided on Thursday with home favourite and world number one Jannik Sinner up against Daniil Medvedev and American Taylor Fritz against Alex De Minaur.
All four players are still in contention for the semis.
