That is the prediction of Sky Sports pundit Peter Fleming, who has been impressed with what he has seen from Djokovic at the O2 Arena in London.
Djokovic clinched his 50th victory of 2018 with a straight-sets win in his opening singles match of the group stages, beating John Isner 6-4, 6-3 on Monday.
The Serbian, who has already been crowned world No 1, has enjoyed a fabulous season so far, something which seemed inconceivable at the end of last year as he was plagued by a recurring wrist problem.
While Zverev has made his mark in the Masters 1000 series over the past 12 months, the German has at times struggled for consistency.
And Fleming reckons Djokovic is the favourite against Zverev, as he is just too strong indoors.
“Djokovic is playing just about as well as he can play or the best he has ever played,” Fleming said when previewing the clash.
“So it’s a tall order too try and beat him indoors where he’s so comfortable and had such great success.
“Zverev looked a little uncomfortable in his match against Marin Cilic, but he dug it out and showed his true competitive instincts.
“He’s a real fighter.
“But he mishit 15 or 20 forehands, so he made a lot of unforced errors and against Djokovic, he won’t be able to get away with that.”
Fleming also thinks Djokovic has an advantage over his rivals as he still looks fresh.
He added: “Yeah he [Djokovic] does look so fresh and he’s worked really hard,” said former American tennis player Fleming.
“He’s had a really good run in and he’s getting more and more confident.
“When you’re winning matches, winning tournaments, your confidence grows and you’re running adrenaline.
“You can run through walls and that’s what he seems to be doing.”
Source : EXPRESS