Fernando Verdasco's marathon Australian Open semi-final defeat to Rafael Nadal in 2009 was the driving factor behind the his shock five-set win in Melbourne on Tuesday.

Verdasco and Nadal played out the longest match in the history of the tournament seven years ago as the 14-time grand slam champion came out on top en route to the championship.

However, after re-watching the 2009 epic on more than 10 occasions, Verdasco exacted some revenge in a 7-6 (8-6) 4-6 3-6 7-6 (7-4) 6-2 first-round victory on Rod Laver Arena.

Verdasco, who rallied from 2-0 down early in the fifth and deciding set as he unleashed a total of 90 winners, told reporters he did not believe he would have another opportunity to square off against Nadal Down Under.

"Of course, I thought many days, many times about that semi-final. You know, it was my longest match ever. It was my first time in semis, and after that also," said Verdasco, who had lost 14 of his previous 16 encounters against Nadal.

"It was of course a tough match to lose after five hours and almost 50 minutes, 40 minutes.

"I didn't really think I would have another match five sets against Rafa here in Australia. I mean, you never know.

"But I honestly didn't think about having another chance or having something like what happened today.

"I think today's match was very similar in terms of even games in the sets, going to a fifth set. But of course the beginning of the fifth I was for a second thinking about that semi-final. I was like, please, I don't want to lose.

"He started breaking my serve. After that, I started playing really good, hitting very hard serve, forehand, and not making many mistakes. So I'm very happy with the way that I finished the match."

Despite being a US Open and Wimbledon quarter-finalist, the semi-final defeat to Nadal has continued to haunt the former world number seven.

Asked if he was frustrated by the fact he is best known for that historic loss, Verdasco added: "Still now they come to me telling me how well I played seven years ago. I'm like, I didn't play again after that? Even last night they told me at the hotel. I'm like, I play against him tomorrow again.

"So many times they came to me and told me about that match. But I'm just happy with how I played today. That was a long time ago. Now I will try to enjoy this victory with my team, have a nice dinner, and then tomorrow also for one day."