England had looked in a strong position at lunch on Saturday after Ben Stokes took the key wicket of talisman Steve Smith, following Stuart Broad's two wickets in two balls early on, to leave Australia struggling on 78-3.
Supported by Travis Head, Khawaja stood firm and led the recovery, celebrating a maiden century on English soil with vigour, before seeing Australia through to stumps unbeaten on 126, alongside wicketkeeper Alex Carey (52).
Khawaja was clean bowled by Broad when on 112, but was handed a reprieve as a no ball was given - a stroke of luck the Australia opener deserved for his determined innings to revive his side's hopes of getting a result in Birmingham.
"I was getting stick from the crowd as I am walking out there saying that I can't score runs in England, so I guess I was a bit more emotional than normal," Khawaja said.
"It's not that I have a point to prove, it's just nice to show I can score runs. I am happy to be out there and show the real me. I don't know why I threw my bat in the air, but that is me.
"The way England batted yesterday was really entertaining. I understand why people like it, but nobody will care how you win, whether you score at three an over or six an over. This is why test cricket is the beautiful."
AUSSIE REVIVAL
England's decision to declare before the close of play on day one took many by surprise, with the move coming under further scrutiny after they failed to take any wickets before close of play.
But the hosts did not need long to make inroads as play resumed on Saturday, with Broad again proving to be Warner's nemesis, the Australian opener playing onto his own stumps for nine.
Ranked the number one test batter in world cricket, much was expected of Labuschagne, only for Broad's swing, in overcast conditions, to find the edge to put England in a strong position.
Smith looked in fine fettle before Stokes, who it was not clear how much he could bowl given his recent knee injury problems, trapped the Australia number four leg before wicket for 16.
Head loosened the shackles after lunch to get the scoreboard ticking over at a rate more akin to England's new aggressive batting approach before being caught just after reaching his half century.
Moeen Ali struck to remove Cameron Green with a beauty of a ball, but Khawaja could not be undone, punching the air as he reached three figures for the 15th time in international test cricket.
Carey reached his 50 late in the day, edging one past the slips as another chance came and went for England, who on another day could have had Green stumped from just his second ball faced and Khawaja out had Broad not overstepped the line.
Instead, the first test, which for much of Saturday looked to be swinging in England's favour, remains finely poised.
