Charlie Wyke's second goal, with 19 minutes remaining, all but ended MK Dons chances of a comeback in their 4-1 defeat to Bradford City on Saturday according to defender Scott Wootton.
Wyke tapped home City's third when Dons, down to 10 men after Aaron Tshibola's fifth minute red card, had fought from 2-0 to get back into it at 2-1 before the break.
With Chuks Aneke and Osman Sow looking to form a dangerous partnership at the other end of the pitch, Wootton felt Dons were in with a chance of getting back on level terms before Wyke's goal, which had hints of offside, ended any slim chances of a turnaround.
"The third goal has killed us," said Wootton. "That goal just before half time took a bit out of them and gave us something to aim for. The longer we kept it at just the one goal, it created a bit of nervousness in them.
"I've not seen it back and we felt it was offside, but it has killed us. We put in a good fight for an hour, and then they were comfortable.
"It's frustrating because we've come into the game in really good form. We've had three clean sheets in a row, 10 points from 12 and we were confident. It's obviously disappointing to be beaten 4-1 at home.
"One thing for sure, when it's 10 vs 11, you need a bit of luck or decision to go your way. It didn't happen for us today."
Wootton, along with George Williams, was blamed by manager Robbie Neilson for the 2-0 defeat away at Peterborough last month - Dons' last defeat before Saturday's hammering - but avoided the finger this time, with it being aimed at Tshibola.
Wootton said: "He was the last man and we can have no complaints about the sending off. He'll know he has to do better. He's made a mistake and has paid the ultimate price."
The defender went on to praise centre-back partner Ethan Ebanks-Landell, who scored his second goal in as many games to bring Dons back in it just before half time.
"He did really well, initially stepping forward and having the shot," Wootton added. "We've worked a lot on set pieces and that was a well-worked one from the training ground, he's got a block on his man and put a great glancing header into the bottom corner. It was very similar to last week.
"And I think we could have scored minutes earlier when Kieran Agard was whiskers away from getting his head on George Williams' header. They're the positives we have to take from the game - we caused them some problems even at 10 vs 11."