But in a matter of minutes on Saturday, and before a single point was played, his veneer of confidence had crumbled.
The 43rd-ranked Tomic, the last Australian standing at his home Grand Slam, was humbled 6-4 7-6 6-1 under the lights of Rod Laver Arena after being reminded by the public announcer whom he was playing.
"A lot of players, when you play these sort of players like Roger or Novak, you lose belief before you get into the match," the highly rated 20-year-old said.
"Eighty or 90 percent of players that play the top guys, like with Roger, you lose your belief.
"I got in there, I started to think after they mentioned all these Grand Slams leading up - Wimbledon champion six times, six times US Open champion.
"Then I was, 'Oh crap, it's Roger'. I tried to block out who's on the other side of the net but couldn't quite do it after that announcement."
Tomic was broken in the first game, his first loss of serve in the tournament, and though he recovered to threaten in the second set, was soundly beaten by a man he described as the "greatest" the game has seen.
It was Tomic's second lesson from Federer at Rod Laver Arena, after being trounced in straight sets in the round of 16 last year.
"You learn something every time you watch him. I learned something tonight as well," he said.
"You use this and you use it in a good way. It's going to make me a better player. I'm going to keep working hard. Point by point, I'm going to get my opportunities this year again and become a better player."