Within days of moving into the manager's office at Sunderland, Martin O'Neill rolled down a sock, raised a tracksuit bottom and instantly dispelled the growing urban myth that his ankle was tattooed with the club's crest.

Tattoos are most definitely not O'Neill's thing but, after spending much of his first 90 minutes in the Sunderland technical area rueing a succession of spurned chances, Steve Bruce's successor must have been seriously tempted to invest in some sort of lucky charm.

In the end none was needed. After too many near misses to remember, James McClean's catalytic debut-making introduction from the bench and Sebastian Larsson's late winner provided Sunderland with only their third home win since New Year's Day. It may be some time before they fulfill O'Neill's vision of playing in the manner of Barcelona but as a banner at the Stadium of Light declared: "Our season starts now".

Steve Kean could look on only in envy as O'Neill, a boyhood Sunderland fan, stepped out to a rapturous reception from an adoring new public. In stark contrast, Blackburn's manager saw an already grim season take yet another turn for the worse as Rovers remained stuck in the relegation zone and his future became the subject of even more conjecture.

Yet if the taunts of "You're getting sacked in the morning" on the final whistle probably left Kean wishing he had never bothered getting up, the afternoon had begun in far more promising fashion, with Rovers exploiting their hosts' weakness in the face of dead balls.

Bruce once revealed that he never rehearsed defending set pieces and although O'Neill spent much of last week aiming to remedy that omission, his players still wobbled in such situations.

Highlighting this vulnerability, Morten Gamst Pedersen delighted in deconstructing O'Neill's homework, his low, swerving free-kick picking out Chris Samba just outside the far side of the penalty area. Stepping inside Phil Bardsley, Samba unleashed a shot which Keiren Westwood could only parry into the path of Simon Vukcevic, who headed it beyond his reach.

Kieran Richardson might have equalised after being adroitly cued up by Larsson's flick and Stéphane Sessègnon's low cross but, left one-on-one against Paul Robinson, he shot straight at the goalkeeper from six yards. In the technical area, O'Neill rocked back on his heels before adopting a head-in-hands pose.

Suddenly Blackburn's penalty area might have been a bagatelle board. As Sunderland rained in balls there were ricochets, rebounds, blocks, scrambled clearances and near misses galore but a home goal stubbornly refused to materialise. Instead O'Neill's players could easily have been two down when Scott Dann headed another Pedersen free-kick into an empty net at the far post. Although Peter Walton disallowed the efforts on the grounds of Samba's perceived foul on Westwood, if anything the visiting centre-half was arguably the man barged into as Westwood charged off his line in a forlorn attempt to meet Pedersen's latest curved ball.

Presumably galvanised by O'Neill's inaugural half-time homily, Sunderland reappeared for the second period in all-guns-blazing mode but, once again, their final ball repeatedly lacked sufficient guile and finesse.

Robinson made a brilliant one-handed save to divert Richardson's goalbound volley but, judging by a succession of extraordinary visiting blocks, it appeared as if Kean's defence were wearing magnetic kit. Desperate to alter the power balance, O'Neill sent on Ji Dong-won and McClean in place of Connor Wickham and Jack Colback.

McClean's advent made a real difference, the young winger – and Sunderland's new manager loves a wide boy – unsettling Kean's defence from the moment his first, excellent left-wing cross was nearly turned beyond Robinson by Sessègnon.

Granted he made three enforced substitutions but it did not help Kean's cause that he had re-tuned Blackburn's tactics on to an extremely negative wavelength which failed to make the most of the central midfield talent of Pedersen and David Dunn, not to mention Yakubu Ayegbeni's capacity to worry Wes Brown and the recalled Titus Bramble.

Deliberately sitting back, Blackburn actively invited the most intense of penalty area barrages. It seemed impossible that they could survive such a blitz unscathed and, lurking outside the area, David Vaughan pounced on Adam Henley's half clearance, beating Robinson with a splendid left-foot strike into the top corner. On the touchline, Sunderland's manager jumped for joy.

When, deep in stoppage time, Mauro Formica handled just outside the area scope for further celebration beckoned. Larsson, one of Bruce's best signings, stepped forward to send a curling right-foot free-kick arcing over the wall. With Robinson confounded, it clipped the inside of the near post before providing the perfect opening to the latest chapter in O'Neill's career.