Tommy Paul gets by pesty Gabriel Diallo in third round at US Open

Tommy Paul might not have the bombastic power of some of the other top-end players on the ATP tour, but what he does have is an abundance of athleticism and moxy. At his best, Paul uses all the tools given him in a way that keeps other players off-balance and allows him to hang around in matches he might not otherwise do.

In his third-round match at the US Open against Gabriel Diallo, Paul needed to muster mixing up serves and getting to well-paced balls more than expected. Diallo, after all, was a 6'8" 22-year-old qualifier who has never done much on the ATP tour. Still, his game translates well to a fast surface. Diallo has an excellent serve and hits everything with force.

What he doesn't do well is hit balls that do not have much pace. Paul's first serve was fine, but it was when he went to a screwball-type second serve that Diallo had real issues. The Canadian would either hit the ball long or into the net and seemed uncomfortable finding a way to land the ball back on Paul's side.

Tommy Paul advances at the US Open to set up showcase match-up versus Jannik Sinner in the fourth round

One of the aspects of Paul's game that is underappreciated is his ability to return serve. He was able to break Diallo several times early even though the Canadian won the first set. This planted enough doubt in the Canadian's mind that he needed to be perfect on his serves that he at times tightened.

Meanwhile, Paul appeared to keep his composure through the four-set match. Paul won 6-7 6-3 6-1 7-6. The American has never been one to explode in an Andrey Rublev way, but every player is capable of beating themselves by overthinking. Paul appeared to simply keep reacting to Diallo.

Next up for Paul is an even tougher match. He will play ATP No. 1 Jannik Sinner on Monday in the fourth round. If the Italian was struggling at all with the reaction to the tennis world learning he failed two drug tests in March, it hasn't shown at the US Open so far. Sinner has been dominant. Paul will need to be at his absolute best to defeat the Italian.

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