The Black Cats are just a point in front of Rovers, who are themselves in the relegation zone.
O'Neill has a reputation for galvanising faltering teams and it his man-management skills, as much as his tactical appreciation, which persuaded Sunderland chairman Ellis Short he was the man for the job after the American businessman sacked Steve Bruce.
His record at Leicester, Celtic and Aston Villa has made O'Neill one of the most sought-after managers in British football.
Add in the fact he was a boyhood Sunderland fan and it is easy to see why many of the north-east club's fans believe O'Neill is the right man for the job.
But the fact the Black Cats have scored just 16 goals in 14 league games so far this season suggests its Sunderland's strikers, rather than the supporters, who are most in need of O'Neill's immediate attention.
"It's been particularly hectic," said O'Neill of his first week on Wearside. "It's trying to get to know players, backroom staff, and they likewise with me. But the excitement is still there, obviously building up to Sunday's game, and I'm looking forward to it immensely.
"There has always seemed to be a good atmosphere around the place, I just think it's a little bit of confidence that has been lost.
"We have to address the goalscoring situation, obviously, and as soon as possible. The backroom staff have been telling me that we have been creating chances in games but have been unable to put them away.
"It puts an awful lot of pressure then to try to keep a clean sheet, which is pretty difficult these days," the former Northern Ireland midfielder added.
Blackburn manager Steve Kean has long been tipped for the axe and even a quartet of goals from striker Ayegbeni Yakubu in last week's 4-2 win over Swansea wasn't enough to stop some Rovers fans calling for the Scot's exit.
"There is an expectation now Martin has gone in there and the fans will immediately be thinking there's going to be a change in the way they (Sunderland) play," said Kean.
"I certainly think there will be an excitement and a buzz about the place but we've just got to go and do our own business."
Victory over Swansea was only Rovers' second league win of the season but if they beat Sunderland they will rise above their opponents and climb out of the drop zone.
"If we win this game we go out of the bottom three and above Sunderland so that's a fantastic carrot to be dangled in front of the players and they are aware of that," said Kean.
"It would continue the momentum and we could then focus on two massive home games against West Brom and Bolton, then going into a tough Christmas period, so it's a great incentive."
Source: AFP
Source: AFP