Manager Marcelo Bielsa says he has no explanation for Leeds' shock 2-1 defeat at home to Wigan.
United looked to be cruising to three crucial points in the promotion race after Patrick Bamford gave them a 17th-minute lead.
The opener came just moments after Cedric Kipre had been red-carded for handling a Bamford shot, with Pablo Hernandez missing the resulting penalty.
But the Latics refused to buckle and Gavin Massey's brace turned the game around, meaning Leeds trail second-placed Sheffield United on goal difference with three games to go.
"There is no explanation why that happened today," Bielsa said. "Destiny gave us a red card, a penalty and 15 chances to score.
"We simply should have won that game today. The conditions were right there for us to win the game.
"It was a game that we had to win but it was a game that we did not deserve to win.
"I take full responsibility for the defeat for not planning the right path to make sure that we did get the win.
"I am sad at this defeat, but I am very motivated. We have had a good season, but it will mean nothing if we do not get promoted.
"This provides the motivation for our next game, we can only heal this wound by getting promoted.
"Brentford is going to be a very tough game for us, but we are determined to make up for this defeat."
Massey cancelled out Bamford's goal just the break before completing a brilliant comeback when he poked home from Leon Clarke's knockdown on 62 minutes.
Wigan keeper Christian Walton then made a number of good saves in the closing stages as the Latics gave their survival hopes a big boost.
Thrilled Wigan boss Paul Cook was full of praise for the battling spirit and determination of his side.
"We are delighted to win and to get the three points," he said.
"When we had a man sent off and then they have the penalty, the first thought was 'how much can we keep them down to?'.
"You would expect Leeds to go on and win the game comfortably, but great credit to the players.
"The last two games have shown the spirit they have and to take four points from Norwich and Leeds is brilliant, they deserve so much credit and respect.
"I do not think it was a red card or a penalty, when people watch it back they will have different opinions, but the referee needs to get things like that right.
"We had a bad five or 10 minutes while Leeds went through us, but once we got to grips with what we wanted to do we carried a threat and our goals came at just the right time."
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