Roger Federer labelled prodigy Alexander Zverev as “the full package” after beating the German to book his place in the ATP Finals knock-out stages.
The world No 2 marched into the semi-finals once again on Tuesday but he made hard work of the task before finally prevailing 7-6 (8-6) 5-7 6-1 in a high-quality battle of the generations with Zverev.
The triumph put the 19-times Grand Slam champion through – the 14th time he has made the last four in 15 appearances – with the tournament still only three days old.
He is now an overwhelming favourite for a seventh crown in the absence of Rafael Nadal, who has pulled out injured.
The best bits from Federer's battle with Zverev at London's O2
Zverev, 20, is yet to make an impact at a Grand Slam but if the third seed overcomes Jack Sock, a Federer reunion in Sunday’s final would seem a distinct possibility.
“What I like about Zverev is he’s got the full package,” Federer said.
“He’s already three in the world. I think he’s going to leave the World Tour Finals, regardless if he qualifies for the semis or not, with a lot of information.
“I think the last six months of the season gave him everything he needs to work forward to. Then, of course, he’s only going to get stronger from here. That should be very encouraging for him and his team.”
Federer reflected on a tough match against Zverev with Sky Sports' Mark Petchey at the Sky Pad
Sixteen years separate this pair but it was concentration and stamina from the 36-year-old’s legs that ultimately proved the difference.
“I think it was a very positive match,” Zverev said. “Obviously he won it, he’s in the semi-finals, but even for me, I played the better match of the two today.
“I think I still have great chances of qualifying, playing Jack Sock next. I think if I continue having this level, I don’t know, maybe you’ll see me on the weekend still.”
The season-ending extravaganza ATP Finals ends another memorable year which will be covered via our website www.skysports.com/tennis with live blogs, reports, reaction and expert analysis as the season reaches its climax.
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