The former winner of all four grand slams was back to his brilliant best, producing a remarkable display of accurate serving, lethal follow-up groundstrokes and breathtaking counter-hitting.
"I've been answering questions about retirement all the time, but not tonight," the 34-year-old quipped after setting up a showdown against Lleyton Hewitt.
The Australian former world number one reached his first final in six months with a routine 6-3, 6-2 victory over Spain's Tommy Robredo earlier on Saturday.
"It's hard to be objective about that," Agassi added, his eyes illuminated like beacons.
"We both brought our game and it was one which could have gone either way. It's been a while. It helps me to believe and comes at an important time. You would have a hard time playing a better match than that."
Agassi also enthused about the atmosphere in the stadium.
"You get a rush of blood and the hair on your body stands up, which in my case is a lot of hairs," he said, running a hand over his shaven pate.
The number 11 seed compared the match to his 2001 U.S. Open encounter against Pete Sampras, which is regarded by many as one of the greatest.
This one was special not only for continual great rallies but for great contrasts.
RODDICK HELPLESS
Roddick's record-breaking serve projected 29 aces which in many cases would have won him the match.
However, Agassi's reflexes and timing enabled him to break it at 6-5 -- the only break of the match -- which gained him the first set, and in the deciding tiebreak Agassi also scored two of the four points on the Roddick delivery.
It was hard for the 21-year-old to take, not only because he was losing a title and suffering a hiccup before the Olympics, but because it was hard to know what else he might do.
Several times Roddick gestured in dismay, once he kicked an advertising board with a loud crash and was booed, and during one change-over he argued lengthily with umpire Norm Chryst, calling him "hopeless".
But this was a testy rather than churlish display by Roddick, who played a full part in an exhilarating spectacle which repeatedly had a full house on its feet.
"You guys had him written off seven years ago," Roddick said.
"He thrives on that. Part of me is happy that he let his racket do the talking -- and it's saying something."
Asked if he was surprised how Agassi returned his serve, Roddick replied caustically: "He's the best returner in the world. It's a bit like asking him if he's surprised that I served hard."
In the first semi-final, Hewitt's play was full of his trademark counter-hitting and fierce refusal to give up any cause, but more unusually it also featured unusually potent serving.
He has still dropped serve only once in the tournament.
"I was just trying to clean up my service games and wait for an opportunity -- and I got it," Hewitt said.
"I feel like I've been playing pretty well for a while now, and here I have been putting results together day in and day out," added Hewitt, who has also beaten Gustavo Kuerten, Tim Henman, and Marat Safin on the way to the final.
