It's semi-final day at the ATP Tour Finals on Saturday, with some rather unlikely match-ups that Dan Weston discusses here...
"These head-to-head matches have been very serve-orientated, with both players holding in excess of 90% of the time, and I'd be surprised if today's encounter didn't follow a similar theme."
Nadal out despite Friday victory
With pre-tournament favourite Novak Djokovic ousted on Thursday, Rafa Nadal joined him on Friday despite a victory over Stefanos Tsitsipas. Nadal didn't face a break point and again, his serve numbers were good, so his elimination will have been a real blow to him - he has the year-end number one ranking to console himself with.
The reason Nadal was knocked out was because Daniil Medvedev was unable to prevent Alexander Zverev from winning with the German prevailing in two tight sets in a match with only two break point chances throughout. Medvedev was arguably unlucky to lose 2-0 given he only won three fewer points in the entire match, suggesting he actually held serve easier, on the whole.
Federer with advantage for anticipated tight match
Again this illustrates the frequently fine margins with which tennis matches are decided and it is very possible that we will see more of the same in today's semi-finals. In the afternoon match, not before 1400 UK time, Tsitsipas has the tough task of defeating Roger Federer today and stats-wise, Federer does have a decent advantage over the Greek man.
Indoors this year, Federer has won slightly more service points but over 8% more on return with Tstisipas' style rather serve-orientated, although Tsitsipas will be able to draw on his success over Federer at the Australian Open in January when priced as a 6.005/1 underdog.
Their matches so far have been tight with Federer's three wins coming in straight sets but either via a 7-6 7-6 or 6-4 6-4 scoreline, and the duo have played five tiebreaks in ten sets completed in their head-to-head series. These head-to-head matches have been very serve-orientated, with both players holding in excess of 90% of the time, and I'd be surprised if today's encounter didn't follow a similar theme.
Federer is 1.384/11 to get the win, which I think is a few ticks too big but nothing untoward. He's also produced better data this week (again, with a decent advantage on return) and I think the market has this about right.
Zverev not far from value for Thiem clash
This is also the case in the night match today (not before 20:00 UK time) with Dominic Thiem a slight 1.768/11 favourite to get the better of Alexander Zverev. To be really honest, the progress of both players is a surprise to me - both haven't got great hard/indoor hard data this year - and for me, Thiem does look like a wafer-thin favourite, although this price does look a little on the short side.
I think anything over 2.407/5 on defending champion Zverev would get closer towards value territory today, so he needs to drift five ticks from his current 2.305/4 price - I'd certainly prefer Zverev than Thiem at current market prices, although my view is that the market line on the German isn't quite big enough.
They've met seven times already prior to today although not since May 2018, and only twice since both were top 10 players (1-1). It's very difficult to look at their first three meetings with any view to today, given Zverev was ranked around the 50 mark in those clashes - a rather different match-up to today's semi-final in the Tour Finals.
Unless there's a drift on Zverev, this looks a match best watched from a pre-match perspective and I'm anticipating another tight encounter - similar to Zverev's win over Medvedev yesterday.
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