It is gospel among tennis fans fortunate enough to attend live tournaments, especially the Big Four majors, that some of the most interesting play often occurs in the early rounds, when several hundred players compete, half of whom will not be seen again; usually on the outer courts, away from the hubbub and most of the ticket-holders. That is where you might see a match between someone such as the Argentine Diego Schwartzman, listed optimistically at 5’7” and 143 pounds, ranked No. 13 in the world and seeded fifth in the draw for the US Open, which got underway Monday, playing the British Cameron Norrie, seven inches taller, ranked No. 77 in the world and unseeded in the tournament.

The two faced off Monday in the tournament’s first round, this year without spectators. As we watched the match highlights (the tournament airs on ESPN channels), we liked the austerity. We felt we could hear the players thinking.

Norrie was new to us and wonderful. He got the top of his racquet on the ball on his serve and seemed to hold it a microsecond longer than usual before he sent it whizzing down the center line and curling away. How he torqued his torso was a wonder. But Schwartzman, whose serve is only so-so, is a dogged defender, and soon Norrie, who had been the top-ranked male college tennis player in the U.S. at Texas Christian University, was down two sets, 6-3, 6-4, in best-of-five play. It appeared he “was being consumed by some existential crisis when he was, in fact, losing a tennis match,” said the Guardian’s tennis correspondent.

“We’re looking at a player who’s in a slightly different class to Cam,” said Tim Henman, the British tennis champion, of Schwartzman.

If they have made it into the tournament, these are superb players. But there seems to be something ineffable that lifts a few into the top ranks and lets them stay. We know it is not size or build or even style of play. Perhaps, without the fans, more will be revealed.

Tennis is single combat. There are not many sports like that; boxing, once enormously popular in the U.S., fell out of favor some time ago. Tennis players still face one another – from across a net and, if they are any good, never losing the peripheral awareness of their opponents even as their eyes are locked on the ball. It is intimate, and more so without a live audience. Players read each other’s tells, get in each other’s heads: “If I spin it wide, he’ll go for the angled return, and I’ll be there to volley it away.” This is ply-thinking, like the way a computer “plays” chess.

Ashton Eaton, the American decathlete who took gold at the 2012 Olympics, was asked before the 2016 games who among all athletes in all sports he thought was most athletic. After decathletes, he said, it had to be tennis players – “Just because of certain things required. Those matches are three or four hours long. There’s the technical aspect, the agility, the mind-body awareness. Not to mention the game itself is a little bit like a chess match.”

In the third set, in the fan-free quiet, Norrie began to climb back. He took the third and fourth sets, 6-2, 6-1, which put the players exactly where they were at the start of play. Now it was Schwartzman’s experience against Norrie’s grit.

Twice Norrie saved points that would have given Schwartzman the match. And then, in that intimate quiet of tennis without spectators, Norrie, after three hours and 59 minutes, at last showed – 7-5, and with no fanfare – what it took to advance one round in the majors. “Well done,” we said to ourselves.