Australian Open Men's Day 4 Tips: Murray a surprisingly big price for second round success

• Nadal shocked by McDonald

• Brooksby can test Djere

• Murray again underdog

Nadal out while Auger-Aliassime scraps

Despite a poor run of form, Rafa Nadal's loss to Mackenzie McDonald definitely has to be filed as being a big shock, and quite where the Spaniard goes from here after the straight-sets loss will be fascinating to see. While most heavy favourites got the job done with minimal fuss, Felix Auger-Aliassime was pushed to five sets by Alex Molcan, with the Canadian needing to fight back from two sets down to win in five. In terms of Auger-Aliassime's chances later on in the tournament, at least it wasn't a long match, taking just three hours.

Ruud facing tricky but inconsistent Brooksby

Moving on to Thursday's schedule, there's the usual array of heavy favourites in action, including the likes of Holger Rune, Taylor Fritz, Alexander Zverev, Roberto Bautista-Agut and of course, Novak Djokovic. However, Casper Ruud faces a tricky test against Jenson Brooksby, so we will get things going with a look at that match.

The second seed is currently trading at 1.374/11 against the talented young American, who has still got an element of consistency to discover but has a very high potential level. After a tough end to 2022, Brooksby has already made the semi-finals in Auckland last week, while Ruud was ousted in the first round of that event in a shock loss against clay-courter Laslo Djere.

With Ruud having vastly superior serve data, but Brooksby's return game showing an edge, the dictating factor as to whether we will see a shock here is if Brooksby can put consistent pressure on the Ruud serve, or take the odd key point or tiebreak. It's certainly possible, and this does look like a really tricky round two match for the Norwegian.

Murray could back up win over Berrettini

Following his stunning win over Matteo Berrettini in a real epic on Tuesday, Andy Murray returns to action, and is yet again an underdog. He faces the home player, Thanasi Kokkinakis, who eased past Fabio Fognini his opener.

Unless we are really sure that those five sets will have had a real physical impact on Murray, I'm surprised to see him as the underdog here at 2.466/4.

Kokkinakis has much better serve numbers, but Murray's return game negates that, and there's not a lot in the data to split the duo - so if Murray is in decent shape, he has a decent chance here in my view.

Cressy and Kudla with underdog chances

Another player who has fitness issues is Diego Schwartzman, whose hip problem caused retirement in his last warm-up event, and then struggled past qualifier Oleksii Krutykh in round one. A four-hour clash against a player barely ranked inside the top 200 is hardly a recipe for positivity, and the market has reacted to this by making opponent Jeffrey Wolf the favourite at 1.608/13. It seems a fair adjustment, but a poor start from Schwartzman would see that price rapidly drop.

Some of the lower-profile round two matches could see a shock, including Denis Kudla at 2.747/4 for his match with Ugo Humbert, who really struggled outdoors last year and had to drop to the Challenger Tour to pick up wins towards the end of 2022, while the big-serving Maxime Cressy, if fit, has the potential to make life very awkward for Holger Rune indeed. Cressy has had a back problem, but if serving well, could well turn this clash into a very high variance encounter, in which case the current 5.609/2 looks big.