Seven days earlier, the Sweden international's missed penalty sparked a fightback which saw Wolves come from 1-0 down to beat the Black Cats 2-1, with the newly-appointed O'Neill watching from the stands at Molineux.
But the 26-year-old made amends at the earliest possible opportunity yesterday when he curled home the injury-time free-kick which completed a similar recovery for Sunderland, with fellow strugglers Blackburn this time on the receiving end. And Larsson said: "I felt I needed to do something and I am happy I got a goal, especially after last weekend."
He added: "It's been a tough week, missing that penalty and turning a game around which we should have won. Of course when you miss a penalty you feel quite responsible."
With 84 minutes gone, the only smiles at the Stadium of Light were on the faces of the pocket of Blackburn fans behind Keiren Westwood's goal.
After a bright start it was the visitors who took the lead in depressingly familiar style for the red and white faithful, as Westwood could only parry Christopher Samba's deflected effort to midfielder Simon Vukcevic, who calmly headed it into the empty net.
It might have got worse for O'Neill's men had referee Peter Walton, much to Rovers boss Steve Kean's astonishment, not blown for a foul by Samba on Westwood as he came for, but comprehensively missed, Morten-Gamst Pedersen free-kick and Scott Dann headed home at the far post.
But Rovers' capitulation was as spectacular as it was unexpected as David Vaughan smashed home a stunning 84th-minute drive to set the stage for Larsson to curl a last-gasp free-kick past Robinson and in off the post two minutes into stoppage time.
Larsson added: "In the second half I was a bit disappointed with my own performance. I got into some decent crossing positions and I couldn't get any good crosses in. I felt I needed to do something and I am happy I got a goal, especially after last weekend.
"In the second half, I don't think I have ever been involved in a game where we have had that much possession. But unless you score goals you are not going to win games, and David Vaughan scored with an absolute wonder-strike and I managed to get one right at the death."
Source: PA
Source: PA