Tomic was left cursing his request for a first-round afternoon match as the pair battled in temperatures of more than 30 degrees on Rod Laver Arena for over four hours. But in the end the conditions may have played into the hands of the Australian, who admitted he played possum in the third set as he saw his opponent begin to fatigue.
"I knew if I lifted my game early, he would have lifted as well and he wouldn't have left go," he explained. "I pretended a little but in the first few games in that third set to not be there as mentally, but in a way to still be there."
The tactic was a far cry from his early form as the 19-year-old seemingly struggled for any sort of game plan, simply returning Verdasco's shots and largely relying on his opponent's unforced errors to stay in the match.
Verdasco pounced on Tomic's poor shot selection and closed the opening set with a solitary break.
The vocal crowd had high hopes for Tomic, who won the Kooyong Classic at the weekend, and he began to show signs of stronger play and greater initiative in the second set.
He broke Verdasco, thanks to an unsuccessful challenge called by the Spaniard, to lead 2-0. But Verdasco swiftly broke back.
Tomic led at 6-5, but dropped a prime opportunity to take the set with one of many drop shots in his game that fell short.
"It's very hard in that position when you're down two sets to love and having three set points in that second set," Tomic said.
"If it was someone else, I think they would have thrown in the towel. I don't know how I found the energy today. I knew I could've beaten him."
Signs looked ominous for Tomic however, early in the third as the Spaniard took the opening game to love.
Tomic rallied and matches went on serve until Verdasco double faulted at 4-4 to hand the Australian a vital break. He did not wait for a second chance, winning the set as the crowd jumped to their feet.
Verdasco showed signs of fatigue in the fourth, but Tomic was pumped, racing to 6-2 and setting up a thrilling final set.
"Had I not done that fitness [running on treadmills for 20 minutes after a match] for the last two, three months, there's no way mentally you can be out there in that heat and turn around a match like that and win," he said.
Tomic credits Verdasco as one of the fittest players on the tour and the veteran was far from done, silencing the near capacity stadium and stunning his opponent with a blistering ace to take the first advantage in the decider.
At 4-4 and 30-40 down, Verdasco challenged a shot at the baseline to save his serve, but there was nothing to argue two games later as his powerful forehand landed well past the opposite baseline to give Tomic a break and 6-5 lead.
Tomic wanted an ace to win the match, but instead he advanced after a 20-shot rally, representative of the duel between the young Australian hopeful and the Spanish journeyman.
"This is probably the toughest five-set match I've ever played," he said. "To be able to turn around a match from a player like that just shows me what I'm capable of in the future."
"So in the future, when I'm down, I can lift myself and give it a go, always."