ATP Miami Day Eight Preview: Isner a marginal favourite to continue title defence

We have quarter final action at the Miami Masters tonight, with the first two matches in the round taking place. Our tennis columnist, Dan Weston, previews the clashes...

Coric bags us another underdog winner

Borna Coric added to our successful tournament so far with another underdog win, overcoming the imploding Nick Kyrgios in three sets in dramatic fashion last night. Kyrgios again showed his prodigious talent - his 'hotdog' winner was certainly one for the highlight reels - but also his questionable temperament. It's difficult to think that he will ever consistently challenge at the top of the sport without addressing these issues.

There were also victories for two other players I indicated as slight value - John Isner and Denis Shapovalov - while there was a considerable shock, with tournament favourite Novak Djokovic being knocked out by Roberto Bautista-Agut. Roger Federer needs to wait until tonight to play his rearranged fourth round clash with Daniil Medvedev.

There are just two quarter-finals on the schedule in Florida tonight, with the market unfortunately looking pretty accurate in both cases.

Isner a slight favourite to continue title defence

In the first match, John Isner is a very marginal 1.98 favourite over the aforementioned Bautista-Agut. It will be fascinating to see how the Spaniard fares after a magnificent comeback victory over the world number one last night, but Isner should have plenty of motivation, given that he's defending tournament winner points here.

It's probably fair to suggest that Isner would have settled for being marginal favourite in a quarter final prior to the tournament started, and my model completely agrees with this market line - I have Isner at 1.95.

The two players haven't met since 2016, and their three meetings have been rather serve orientated so far, with Isner winning an impressive 72.5% of service points. It looks like Isner's serve-orientated style has influenced the service and return points won percentages in these historical head to head matches to a greater extent than Bautista-Agut's more return-orientated dynamic, so I'd anticipate the match having few breaks and break point chances - whoever converts their few chances will likely triumph.

Prospects Auger-Aliassime and Coric accurately priced

Following this, the night match features two players who have done well for this column during the tournament, with Felix Auger-Aliassime facing Borna Coric. The Croatian talent, Coric, is correctly chalked up as a 1.81 favourite to take this - my model went 1.78 in his favour, and it is difficult to consider any viable pre-match angles to work with here.

Coric's edge stems from a slight advantage on 12 month hold percentages on the surface, with return data for the duo pretty similar, although it's worth pointing out that Auger-Aliassime's hard court data in main tour matches in 2019 so far slightly eclipses that of Coric.

However, it would be a bit of gamble relying on this small sample of data to side with Auger-Aliassime here, so my advice is that this is a match best watched - at least from a pre-match point of view - and I'm anticipating a high quality match between two of the best prospects on tour.