Picking spots crucial in opening round
As always with Grand Slams, the opening couple of days are extremely hectic, with 32 men's singles and 32 women's singles matches on each of the first two days. With this in mind, picking spots is as crucial as ever, and this is especially the case in the opening round of tournaments, where player condition is often a little questionable. Given this, I'd certainly recommend caution in the opening round, particularly where staking is concerned.
Initially, I want to open with some thoughts about the underdogs on the card, and some reasons as to why they might be a little under-rated by the market.
Berrettini capable of pushing Tsitsipas
First up is Matteo Berrettini, who stands at 3.8014/5 to get the better of Stefanos Tsitsipas. The Greek prospect, Tsitsipas, still has much to prove on hard court (98.4% combined service/return points won percentage in the last six months, despite winning 12 of 19 matches), and a major reason for this winrate has been a 6.1% overperformance on break points on return. This should mean-revert in time, and against a promising opponent, he might have some difficulty - the worry for Berrettini is that he's lost a lot of tight three-setters on the main tour, and I wonder whether he might be able to sustain his level during a long match.
Kudla an uneasy favourite over Polmans
I also feel that home player Marc Polmans, who tends to ply his trade on the Challenger Tour, could represent value at 4.2016/5 against Denis Kudla, whose data really isn't anything special, while if Adrian Mannarino (pictured below) can get back to nearer his best - far from a given based on his current level - he could test Kevin Anderson, with the Frenchman available at 10.009/1.

Basic value against mediocre Laaksonen
The other underdog I like is Mirza Basic (pictured below), who at the time of writing is 2.1211/10 on the Exchange.

The Bosnian takes on Henri Laaksonen, whose level has dropped alarmingly in the last year or so. Basic does his best work in quick conditions, which he won't necessarily face here, but still looks competent enough based on his hard court data - certainly compared to his opponent, who has only won 40% of his matches on hard court at Challenger level in the last 12 months, with a combined service/return points won percentage well below 100%, even at the lower level.
On this basis, it's a simple value play on Basic, and I'm not remotely surprised that he's shortened a little since I priced the match up on Friday, although he's still easily enough value, based on my numbers. He's today's recommendation.
Monfils looks a value favourites despite condition doubts
As for potential value favourites, if Gael Monfils is in remotely decent condition, he should have too much for Damir Dzumhur, whose hard court data is dire, and the enigmatic Frenchman's price of 1.548/15 reflects that caution from the market about that condition.
Serve likely to dominate in Opelka and Isner clash
Finally, John Isner (pictured below) looks some value at a similar price, as he faces Reilly Opelka in what is undoubtedly the most serve-orientated match of the day. A player so limited on return in Opelka is unlikely to be able to make much impact on arguably the best serve on the ATP Tour, so the young American had better gear up to win tiebreaks, if he is to progress into the second round.

The 10/11 available with the Sportsbook on over 12.5 games in the first set looks tiny value, but not enough to be actionable - evens plus would be a decent play here.
Murray among big names in action
In other matches, a number of big names are in action. Marin Cilic, at 1.3030/100, faces Bernard Tomic in what is a tricky-looking opener, while Rafa Nadal is in action, also against an Australian, as he takes on James Duckworth. Roger Federer is another very heavy favourite, meeting the Uzbek, Denis Istomin.
We also see Andy Murray meet Roberto Bautista-Agut, and after his announcement on Friday, could this be the Scotsman's last professional match? The Spaniard is 1.232/9 to oust Murray, which looks about right given the fitness issues so obviously bothering the former world number one. No doubt many will be following this match with interest.
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