Usman Khawaja looked comfortable at Test level from the very first ball he faced.

Facing gangly quick Chris Tremlett, outstanding in England’s 2011 Ashes victory on our shores, Khawaja calmly turned him off his hip for two.

The SCG crowd, desperately looking for a beacon of hope in a poor Australian team, roared.

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Khawaja’s second ball was even better.

Tremlett dropped it in short and the 24-year-old didn’t hesitate, rocking back and producing a cracking pull shot that ran away for four.

The big crowd, and the fact he replaced the injured Ricky Ponting – surely the second-best batsman this country has ever produced – did not deter him.

This was some introduction.

He played another excellent pull shot and thrashed a square drive for four before falling for 37, when he top-edged a sweep off Graeme Swann.

But this was not just any old 37.

It was a classy knock played by a man dripping with potential.

Unfortunately for Khawaja, potential became a dirty word, and he struggled to shake the ‘looks good at the crease but doesn’t score big’ tag.

And it speaks volumes that before his hundred against New Zealand at the Gabba on Thursday, that 37 was probably his most memorable innings for Australia – even if he scored a crucial 65 in a successful run-chase of 310 against South Africa in 2011.

Khawaja shared his first century with good mate Steve Smith. Photo: Getty

Prior to the Gabba Test, that was one of just two fifties in his stop-start nine-match career, in which he averaged 25.13 and had been dropped three times.

A move away from the ultra-competitive New South Wales set-up has improved Khawaja’s game, though, as it has done to so many players before him.

He was in excellent form for Queensland before tearing his anterior cruciate ligament in his left knee last year and he impressed again on Australia A’s tour of India in August.

That meant that another call-up to the Test side was on the cards – and the retirements of Chris Rogers, Michael Clarke and Shane Watson left the batting order needing replacements.

So, like they had done three times before, Australia’s selectors took a gamble on Khawaja.

They hoped that his timing, footwork and ability to make the game look easy would stand up on the big stage.

And it certainly did.

He immediately looked in good touch on the opening day of the first Test against the Black Caps, punishing one of many bad balls from off-spinner Mark Craig with a punch through gully for four.

He pounced on a short ball from Trent Boult and then hit a glorious off-drive off Tim Southee that had all the hallmarks of a 100-Test player.

From that moment, it was clear. Usman was on.

Craig kept serving up garbage and Khawaja was more than happy to take advantage, getting down the track to hit two sixes before he reached 50.

And while he scored quickly, this was far from a slog-a-thon.

He hit late cuts, cover drives, on-drives and then, to reach that elusive century, swatted Boult down to fine leg for his 12th four.

Khawaja punched the air with his helmet, looked to the sky and raised his bat before sharing a hug with skipper Steve Smith (41 not out).

He had done it. Usman Khawaja is a Test centurion.

“It’s what I’ve always dreamt about, I think I physically actually dreamt about it once,” Khawaja confessed after play.

“And then I woke up and it was a horrible day.

Khawaja dreamt of his first test century his whole life. Photo: Getty

“So I’m glad it actually came to fruition, and hopefully I don’t wake up in the next five minutes.

“I’ve wanted to get a Test hundred for Australia my whole life, and there were times over the past four of five years I thought it might not happen. I’m lost for words.”

Khawaja was also keen to share the limelight with openers David Warner (163) and Joe Burns (71).

Much was made of the threat of seamers Southee (1-63) and Boult (0-90), particularly with the new ball, but Warner and Burns nullified them early and that had a huge impact on proceedings.

New Zealand’s lack of bowling depth was badly shown up as a result, with Craig (0-96) and Doug Bracewell (0-79) going for plenty, and Jimmy Neesham and Kane Williamson rarely threatening.

“The hard work was done at the top by ‘Davey’ and ‘Burnsy’, and they batted beautifully,” Khawaja added.

“It allows us at number three and number four to come out and play a few more shots because the ball is a bit older, and the bowlers are a bit tired.”

New Zealand fielded poorly and bowled worse in a dreadful start to their tour.

And when they come back on day two, there’s still eight wickets to get.

One is Test cricket’s second-ranked batsman: Steve Smith. And the other is Usman.