Hometown hero John Millman has stormed into the second round of the Brisbane International after overcoming American Tennys Sandgren.

Millman displayed superior fitness and composure to prevail 7-6 (8-6) 6-7 (6-8) 6-0 against the world No.61 in the first round on Monday.

Millman was broken in the third game but broke back three games later on the way to taking the first-set tiebreak, with the second set unfolding similarly before the American forced a decider.

The Queenslander took back momentum by taking advantage of several Sandgren service errors, breaking him three times in the third.

He will meet Grigor Dimitrov likely on Wednesday, with the sixth-seeded Bulgarian ending his run in Brisbane last year in the second round.

After reaching the top 40 for the first time on the back of beating Roger Federer at the US Open in September, Millman said he felt no added expectation from the Pat Rafter Arena crowd after a breakout year.

“There’s always pressure here. Not necessarily extra pressure,” he said.

“I do feel an extra responsibility playing here.”

Millman has never reached the quarter finals in Brisbane, losing in the round-of-16 in his last three attempts.