Steve Smith took a sleeping pill to settle his nerves but still only managed four hours' kip as he obsessed over his decision not to enforce the follow-on in Adelaide.
The Australian skipper's relief was palpable after his side snared six wickets in the opening session on day five toclaim a 120-run victory and a 2-0 lead in the five-Test Ashes series.
Smith's contentious call to not make England bat again was compounded on Tuesday evening when he burned two reviews in quick succession and dropped a catch in the slips.
"I had to have a sleeping pill last night. It has been a pretty tough 24 hours if I'm being honest," he said on Wednesday.
"It's all part of being captain of your country. You have to make difficult decisions and sometimes you're going to make the wrong decision.
"I'll think back and reflect over the next day or so and think what I could have perhaps done differently and could have done better, and areas that I can continue to improve in my leadership."
Former Australian paceman Jason Gillespie on Wednesday said Smith had been "thrown under the bus" by his own camp over the decision not to enforce the follow-on.
Australia's bowling coach David Saker had questioned the call after England got within 178 runs of victory at stumps on Tuesday.
