Federer cruised past Jack Sock on Sunday in the opening singles match of the tournament, relishing the surface which has been quickened since last year.
And thanks to Sock’s comeback victory against Marin Cilic earlier today, the Swiss can reach a record 14th ATP World Tour Finals last four with a win over the German.
The 20-year-old meanwhile could not achieve a simlar fate with a win as he still has to play the 1-1 American on Thursday in a match that will likely be a de facto quarter-final.
But Zverev would nevertheless relish beating Federer as a standalone result – the victory would give him a 3-2 head-to-head record over the Swiss world No 2.
Federer vs Zverev LIVE
7.55pm: Right then, Ryan Harrison and Michael Venus have wrapped up their place in the doubles semi-finals which means Federer and Zverev will be out on court in just a few moments.
Meanwhile, David Bowie’s “Heroes” blares out on the sound system which is, and I’ve said it before, exceptionally loud. I think that’s supposed to make it more fun?
7.45pm: With Rafael Nadal sitting in a hotel somewhere with his knee on ice, this tournament is supposed to be Federer’s to lose.
The six-time ATP World Tour Finals champion looks comfortable, composed and powerful on court at the moment and is an overwhelming favourite to add a seventh crown.
However, Zverev is not to be underestimated. He’s beaten Federer twice in his career, once on the grass of Halle and once in Montreal, although that came when the Swiss was obviously hampered by a back problem.
They should be walking out at 8pm for a start at around 8.15pm.