Crawley boss Steve Evans insisted that Manchester United were forced into changing their tactics during his side's FA Cup fifth-round defeat.
Sir Alex Ferguson's team won the match 1-0 thanks to Wes Brown's first-half goal, but they were second best to the non-league side after the break.
"The best manager had to think in the second half," he told BBC Radio 5 live.
His relieved counterpart Ferguson added: "They deserved a draw given their second-half performance."
Evans insisted that his side's growing dominance forced United to change their personnel on the pitch and tactics, but the home side claimed injuries to Anderson and fellow Brazilians Fabio and Rafael Da Silva resulted in the tinkering.
The Blue Square Bet Premier side, currently second in their league, went close in the second half through David Hunt and Matt Tubbs, but it was Gateshead-born striker Richard Brodie who had the best chance when his looping header struck the United crossbar in stoppage time.
"It looked like a big chance," added Evans.
"Some of the boys said they thought it was in and I think a few of the United players felt the same way.
"We go home disappointed tonight. We really thought we could win."
The former Stamford and Boston United manager also paid tribute to fellow Scot Ferguson and United's hospitality.
"He gave me a proper Glasgow welcome," added the 48-year-old.
"They way he and his club have treated us makes me proud to be from the same city.
"He gave me a bottle of wine to share with my wife and overall, it was a fantastic experience.
"It was an education how to treat people. It is why they are the best club in the world."
Ferguson, whose has led United to five FA Cup titles, said his that some of his players "maybe didn't understand what FA Cup football is like".
"There is no doubt a few players did not do themselves justice," said the 69-year-old.
"I had no complaints in the first half, I thought we did okay - but we weren't at the races in the second. We were second to every ball.
"It was disappointing. We had some players who maybe don't understand what FA Cup football is like. For them, that is the biggest lesson."