Since the last time they met he had lost the Tottenham Hotspur job, won a court case and been jilted by England, so it was perhaps no surprise that QPR's new manager remained locked deep in conversation with his fellow warhorse until they adjourned to adjacent technical areas.
While the track-suited O'Neill cut a relentlessly hyperactive touchline figure, the way Redknapp continually dug his hands into the pockets of his new QPR club anorak suggested he had made a tactical error in not opting for the full-length maximum-tog duvet coat.
They say that the winter winds which hit the North Sea coast at Sunderland blow in all the way from the Russian Steppes and during a raw, wet evening's chillier moments Rednapp must have wondered if he had not somehow ended up coaching in Ukraine after all.
He turned down that national job for a west London club harbouring reputedly the most divided, discordant dressing room in the Premier League but a combination of "new-manager syndrome" and Harry's galvanising charm seemed to have QPR playing with definite spirit if not exactly stellar sharpness.
Their cause was helped by palpable home nervousness exacerbated by an increasingly edgy crowd. O'Neill's side were on a dispiriting run featuring two Premier League wins in 20 games and almost immediately were forced to regroup when Lee Cattermole limped off with knee trouble. Sunderland's captain and key midfielder had hobbled off in similar distress with the other knee during Saturday's defeat to West Bromwich Albion and it was perhaps a measure of the manager's desperation that O'Neill took the gamble of starting him.
Although the Saturday night rumours that spread like wildfire across Twitter suggesting the Northern Irishman had resigned were entirely erroneous and Ellis Short, Sunderland's chairman, was swift to offer the manager reassuring support, these are unexpectedly uncomfortable times for O'Neill. The last thing he needed was Redknapp to succeed where Mark Hughes had spent 11 months failing, and win an away game.
Winning any sort of league match has proved beyond QPR this season but they held their own here, even if Sunderland's left-back Danny Rose looked the best player on the pitch and Júlio César had to excel to beat away Steven Fletcher's left-foot shot following a deceptively clever reverse pass from his subsequently withdrawn team-mate Adam Johnson.
Only a few months ago it seemed one of the items in Redknapp's in-tray would be unlocking Johnson's mislaid talents ahead of the next World Cup in Brazil. Yet instead of wearing Three Lions on his shirt the man who might have been England manager was sitting alongside Anton Ferdinand and the rest of the QPR substitutes taking shelter from the second half's driving rain.
This time last year, of course, Redknapp was in charge of an exhilaratingly high-flying, title-challenging Spurs side starring Gareth Bale, Luka Modric and Rafael van der Vaart. Precisely how, he could have been forgiven for wondering, had it come to this?
At least he could take heart from the statistic that Sunderland's last three league wins – against Fulham and Wigan this season and Hughes's QPR last term – have come against teams reduced to 10 men. Then there was the knowledge that in 18 previous meetings with assorted clubs, O'Neill had beaten him only once.
Further reasons for cautious optimism began emerging. He may not exactly be Modric, but Adel Taarabt, QPR's outstanding individual, was showing off some promising touches. Similarly while replacing César – who tore a groin denying Fletcher – with Rob Green may not have been the first substitution Redknapp had envisaged making, the goalkeeper discarded by Hughes did well, impressing when cutting out Craig Gardner's dangerous cross and then saving a Fletcher header.
Redknapp has never been afraid to make bold switches and sensing Taarabt was tiring, he replaced the Moroccan – treated to a diplomatically avuncular pat on the back and little word in the ear – with Shaun Wright-Phillips.
Despite a bright cameo, that substitution failed to inspire a debut victory but while Redknapp will be happy enough with a point in the Wearside rain, the wholesale boos which greeted the final whistle served as a reminder that O'Neill is badly in need of an arm round the shoulder right now.
How much longer Short will continue to provide it remains to be seen.
guardian.co.uk © Guardian News and Media Limited 2010
image: © apasciuto
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