Erik ten Hag claimed Manchester United are now a "different team" to that which began his reign with a dismal defeat to Brighton and Hove Albion, ahead of Sunday's FA Cup semi-final against the same opponents.
Last August, Ten Hag became the first United boss to lose his first Premier League game in charge since Louis van Gaal in 2014, as Pascal Gross scored twice in Brighton's 2-1 win at Old Trafford.
That result was swiftly followed by a crushing 4-0 defeat at Brentford, but United have since recovered to lift the EFL Cup and lead the race for final two top-four places.
On Sunday, Brighton will attempt to deny United a place in a record-equalling 21st FA Cup final, and Ten Hag believes the Seagulls will be facing a much-improved team at Wembley Stadium.
"I've heard from many experts and the fans that we've made progress and developed," Ten Hag said. "We're a different team now, but we know we have steps to go. That's quite clear.
"I can speak after Seville, it's quite clear. No team always plays at the highest level, I know, but even if you don't play at the highest level, you still have to win. That is what we have to learn."
The FA Cup represents United's last chance to win a second piece of silverware in Ten Hag's debut campaign, following Thursday's dire Europa League elimination at the hands of Sevilla.
Having described United's performance in that game as "unacceptable", Ten Hag was asked whether he replicates Alex Ferguson's use of the 'hairdryer treatment' following poor displays.
"Sometimes yes, I can go strong in certain situations," he said. "It's a tool, but it's about the timing.
"You need to know when to use it. As a coach, you can pick many communication styles, and this is one of them.
"[On Thursday], you could tell I was really mad. For me, it was so unacceptable. You can make a mistake, but you have to carry on.
"If you play in the quarter-final of the Europa League, you have to give everything and we didn't.
"For any club in my view, that is unacceptable. As a manager, I cannot accept that my team is not giving its best. I would never accept it and the players were made aware of this."
