Two-time ASB Classic champion John Isner knows how fickle tennis can be.
He almost had his bags packed early for Melbourne and the Australian Open on Wednesday afternoon after battling to find a rhythm during his second round match at the Auckland tournament.
The 208cm US giant had been outshone for much of the day by Tunisian Malek Jaziri's stellar serving and passing shots.
Yet he managed to string together three clutch backhand volleys in the tie break to claim victory 6-3 3-6 7-6 (8-6).
"I was not displeased with how I played out there. But ... I very easily could be on a flight to Melbourne tomorrow," he said.
"I've got to kind of trick myself into thinking I'm playing with house money considering that I could very easily be out of this tournament."
His victory in his first match in two months came on a day when many of his fellow top seeds did not get a second chance.
Top seed and defending champion Roberto Bautista Agut earlier pulled out with a stomach bug, while sixth seed Feliciano Lopez also withdrew and No.3 seed David Ferrer crashed out.
It was drama not lost on Isner who said he now takes a 'nothing to lose' attitude into Thursday's quarter-finals where he meets compatriot and good friend, No.7 seed Steve Johnson.
"I should have some confidence stemming from the fact I got through an extremely tough match," he said.
"(But) I don't look ahead, I'm not good enough," he said.
In other quarter-final clashes on Thursday, Ferrer's conqueror Robert Haase meets Portuguese world No.44 Joao Sousa, while 2015 champion Jiri Vesely meets entertainer and eighth seed Marcos Baghdatis.
US fourth seed Jack Sock, meanwhile, takes to centre court for the evening match against Frenchman Jeremy Chardy.