Tuesday brought out the fighter in Sam Dastyari: the fast-talking Labor firebrand, the bank-basher, the media darling with a cheeky grin never far from his face.

Having invited reporters to an alfresco ambush outside NSW Parliament, the sunny Sydney day seemed to promise renewal, survival and even strength.

"Thanks for coming," he enthusiastically greeted the ABC's Leigh Sales. "Quite a privilege to have you at one of my press conferences."

Through 25 defiant minutes, Dastyari was apologetic, sympathetic and energetic. The 33-year-old, whose star had risen so quickly but fallen much faster, acknowledged his sins but declared he wasn't going anywhere.

By Wednesday, all traces of flamboyance had disappeared. In the bland Bligh Street office of the Commonwealth Parliament, he barely flashed a smile as he took the podium.

"I'm going to be making a short statement and I won't be taking any questions," Dastyari began.

Then he paused. A proper, hearty pause - replete with deep breaths - that felt so much longer than its full five seconds.

"This has been a difficult week," he understated. "And this afternoon I have made a difficult decision." Just weeks after ascending to the shadow frontbench, Labor's beloved boy was gone.

Tuesday's mea culpa was supposed to be an act of cleansing. He was in "no rush" to leave, he announced, promising to take every question and leave no stone unturned. And over the course of half an hour he pretty much did, even if the answers often left much to be desired.

Come Wednesday, it was clear the cleansing had been a botched job. The reckoning was much swifter - Dastyari spoke for just two-and-a-half minutes, reading his scripted remarks. And press pack, having watched a man fall on his sword, were denied the opportunity to twist the blade.

"I'm not a shy person," he acknowledged. "I have never been afraid of the spotlight."

But the spotlight had become too bright, and burned too hot. So there was only one thing left for Sydney Sam to do - exit, stage right.

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