Losing Liam Cooper to a red card just before half time meant Leeds faced a daunting second 45 minutes in Manchester against the Premier League leaders, despite holding a one-goal advantage thanks to a Stuart Dallas strike.
Leeds held firm though and even when Manchester City levelled with 14 minutes left did not lie down and then stunned the Citizens by scoring a winner in injury time, Dallas striking again.
Whelan was hugely impressed by the desire of Leeds to go for the win even when at risk of defeat, and is clear that Whites sides of old in recent years would have collapsed.
He said post match on BBC Radio Leeds: “A Leeds United side of old would have crumbled, would have actually capitulated and it would have been three to them.
“This team is completely different with that fight they have, that togetherness they have, that willingness not to lose.
“But then to go and win the game just shows a completely different side to this team that it’s never over.
“They don’t want to settle for a draw.”
Leeds are next up against current champions Liverpool, who are scrapping to finish in the top four to save a disastrous campaign.
The Whites played out a thrilling 4-3 loss at Anfield against Liverpool at the start of the season.
