Rios seemed on the point of retiring after taking an injury time out only five games into the final, but persevered, with a wince here, a grimace there, and prevailed, 6-4, 2-6, 7-6, 5-7, 6-3, after two hours and 55 minutes.
Between back spasms, the 23-year-old world No 3 from Santiago treated the spectators to some spectacular action. On the concluding point of the opening set he sprinted to deliver a forehand winner down the line, his momentum causing him to leap the perimenter boards. During the sixth game of the second set, Rios hit a winning smash from a sitting position before falling on his back. Once or twice, he kicked the ball in a style that would have been a credit to David Beckham.
Agassi, asked by a German television presenter what is was like playing against a handicapped opponent, replied that if that was the case he would not like to face a healthy Rios. "He ran his ass off," Agassi said.
The American himself was not as fresh as he would have liked, having spent three hours and 40 minutes the previous afternoon winning his semi- final against Karol Kucera, of Slovakia, in five sets.
Agassi, whose entry on a wild card was criticised, rose to the occasion, blowing away the Frenchman, Cedric Pioline, in 34 minutes in his first match, 6-0, 6-0, and thrilling the crowd in the epics against Kucera and Rios. "I'm playing aggressive tennis again," said the 28-year-old Agassi, who won $650,000. "That's the key to my game, taking it to my opponent and not waiting for them to miss. This week I really started feeling like I can be the best again."
The match went through a strange passage after the opening set when both players appeared to be trying to conserve energy. "I can't speak for Marcelo," Agassi said. "He has a tendency to kind of look a little lethargic at times, but more out of attitude than out of self-preservation. I didn't really believe he was close to defaulting. I try to base it on his performance rather than what he's doing on the side of the court. I knew the best chance I had was just to go hard. If it turned out that we had a long match, just do my best not to die. I tried to go hard from start to finish.
"I definitely was a little off physically, but I was committed to trying to get the job done. As the match wore on, I wasn't going for my serve as well as I'd like. That hurt me in the fifth set.
"When I got up in the second set, he looked like he idled down a gear. But I knew that was only going to last as long as the set, that he would stir it up again in the third, which he did."
After recovering a break of serve for 3-2 in the final set, Rios had the good fortune on game point for 4-2 to see a ball hit by Agassi teeter on the net cord before dropping wide.
Rios said he started to feel twinges in his back the previous night and twice thought that he would not finish the match. "I had this before, it's like the nerve or the muscles get inflamed. I think Andre says, `This guy isn't injured'. I think I'm the only one that knows what's going on. At one stage when I was going to retire, the trainer said, `No, let's give it one more try'. I won a lot of confidence in the tie-break [7-1]. Even if I was not feeling good, I played one of my best matches. I'm really proud I can win a match like that."
Try trauma hot cream, but do not expect miracles. "The magic's in the fingers," said Alex Stober, the trainer, who paid six visits to Rios during the changeovers.
Venus Williams received $800,000 as the inaugural winner of the women's event. The American defeated another 18-year-old, Switzerland's Patty Schnyder, 6-2, 3-6, 6-2, after an entertaining final which lasted 94 minutes.
In common with Rios, Williams said she would put the money in the bank. "I have to pay taxes, too, you know," she said. "It's not all mine."