Craig Gardner, James McClean, Stephane Sessegnon and David Vaughan all found the back of the Latics net in a commanding performance, with Hugo Rodallega scoring a consolation for Roberto Martinez’s men.
Given the effort his team showed to beat Manchester City 1-0 on Sunday, O’Neill was impressed with his team’s attitude 48 hours later.
“I told the players in the dressing room that I actually thought it was our best performance of the season, the best win since I have been here,” he told Sky Sports.
“For every reason under the sun – the players were out on their feet after the game against Manchester City and it felt as though we had played three games a couple of days ago.
“We have come here with a day less to prepare, which is very difficult, but the players have summoned the strength and determination and courage in their performance tonight.
“I thought it was really fantastic. I just don’t know where they found the energy from,” he stated.
The win lifts The Black Cats up to 10th place in the Premier League standings, whilst Wigan are stuck in the relegation places in 18th.
By Gareth McKnight