The dual grand slam champion prevailed 6-3, 4-6, 6-2 against his fellow 31-year-old, Kunitsyn's main draw spot coming as the lucky loser in place of another veteran, Radek Stepanek, the Czech having withdrawn earlier in the day with an eye infection. From Hewitt, there were a few vintage 'c'mons', and a fighting third set comeback after the match appeared to be slipping from his grasp. A win though, and the former No.1 will take it.

"I didn't know, obviously, that the opponent was going to change,'' said Hewitt, who next plays Denis Istomin of Uzbekistan. "I only found out lunchtime-ish today, so when you've been preparing three or four days to play someone and then it changes, it's always tough, and especially playing a guy who's played a couple of matches in these conditions as well and he's a good ball-striker and had nothing to lose, so I felt like it was a pretty high-standard match out there tonight.''

The only previous match between the pair was the famous round-robin encounter at the 2007 Adelaide International that the Russian won in three sets, leaving the then-21st-ranked Hewitt so incensed that he vented his rage on coach Roger Rasheed at courtside. Rasheed resigned after a locker-room confrontation later that tumultuous night, saying in a statement that it was impossible to achieve the desired results "in the current environment''.

This match was rather less dramatic, and could have finished far earlier had Hewitt not missed a routine backhand volley on break point in the sixth game of the second set, having taken the first in 32 minutes. From the possibility of 4-2, he was broken three games later, as the Vladivostok native took the initiative, and carried the momentum through the early stages of the third set, before Hewitt found something more.

The Australian's career has delivered two grand slam titles and 80 weeks as the world No.1 but only, until now, Davis Cup matches on Pat Rafter Arena. The tournament's previous incarnation was in Adelaide, until the amalgamation with the Gold Coast women's event and shift to the new Queensland Tennis Centre in 2009, and it was in Adelaide that Hewitt claimed his breakthrough title as a 16-year-old in 1998, and again in 2000.

It is hard to see him winning this one, with world No.3 Andy Murray in the field, but stranger things have happened. Hewitt says his body is as healthy as it has been in several years, and his mind is as sharp and eager as ever. A wildcard reflects his current ranking, 83rd, rather than his level when mercifully injury-free, as he has been since resuming from major toe surgery at the French Open in May.

"What I did last year at the Australian Open, my close-knit group probably thinks it's one of my greatest achievements, consdiering how bad my foot was, so just to make it through to the fourth round of the Aussie Open and obviously have a great match with Novak (Djokovic),'' Hewitt said later.

"So for me it's just refreshing to be out here and be pain-free and enjoy competing and moving on the tenis court and not grimacing and in agony every second point, so I'm just really enjoying it. I love the training, I'm still motivated - people ask me why I'm still motivated, I don't know - but once you're retired you're retired for an awfully long time, so I've got a pretty good job out here.''