Anybody who wasn’t obsessed enough to stay up until 12:30 last night to watch US Open tennis missed an increasingly rare joy in today’s sports world: a truly admirable athlete showing what real champions are made of.

Most people are by now aware that this is Andre Agassi’s last tournament. Most people are aware of how he has evolved from punk to sportsman and even statesman, how he is now the model of decorum on the court and the model of a charitable, public-spirited citizen off the court, complete with a mostly self-financed, incredibly successful charter school that he founded and oversees.

And many, if not most, are aware of how he has struggled with back problems and sciatic nerve problems all year; how he has not been healthy enough to play enough tennis to get his game sharp.

So it was last night that when I turned on the match he looked down and out. After losing the first set 6-7 and winning the next 7-6, he was in the process of losing his fourth straight game to fall behind 4-0 in the third set. He looked lost, and he seemed to be moving stiffly. But then it was as if he turned on an inner switch. All of a sudden, his look changed. I swear his pupils got smaller, almost as if focusing inward. He started moving so fast BETWEEN points it was as if he was an Everready Bunny. And he started slogging his way back.

Boom, bing, bang: From 0-4 he moved to 4-4. His opponent, the powerful and quick-wristed Andrei Pavel, steadied himself a bit, but Agassi would not be denied. Agassi pulled out another tie-breaker, 8-6, and that was effectively the end. Agassi then won the first four games of the next set and eventually prevailed 6-7, 6-6, 7-6, 6-2. The sheer grit of the comeback was astonishing. And he did it with class, with self-control, with decorum. Let’s hope he can continue such performances for an entire fortnight.