Cowley was bowled over by United's all-action performance.

"We had to hang onto Leeds in the second half," said Cowley. "We saw the best team in the league playing at the top of their game today. They were relentless at times.

"I've had 13 years as a manager, and that was right up there in terms of an opponent's performance. I thought they were outstanding.

"That was a blueprint in terms of their physical quality and intent. They have so much purpose."

Continuing to wax lyrical, Cowley added: "I actually really enjoyed it in a sadistic way. He's a genius Bielsa. If you are going to be outmanaged, then be outmanaged by a genius.

"I'm not sure we've ever got to that level of performance that Leeds did today. You look at the energy and intensity. He must be relentless in his demands of them to play with that physical output.

"I will be interested to see how the Premier League copes with them when Leeds go up."

Asked whether he felt Leeds would be promoted this season after 16 years away from the top flight, Cowley said: "Absolutely! They're the best team in the division. It was a painful but a great learning experience for us."

A thunderous volley off the underside of the crossbar after 160 seconds from Ayling set Leeds on their way, although they failed to add to their tally until Bamford's 13th goal of the season six minutes after the restart, ending his seven-match drought.

Bielsa believes his side face an anxious run-in, recognising they blew their chance of automatic promotion last season with five defeats in their last nine games.

Asked whether the final stages of the season would again be the most difficult, Bielsa said: "Yes, but that depends on the results.

"Maybe the competition will finish with the last match, maybe before. We have 27 points left to play for, and we don't know how many we are going to need, but we have nine matches to get them.

"Of course, there will be anxiety until we get what we are looking for, but this is the same for every team in the league.

"The most important now is what happens when the competition gets to the finish. A few months ago we had 11 points difference (to the play-off places) and we lost it. What we have to do is wait until the end to see what happens."