Marcelo Bielsa claims some of the Premier League's top teams possess the X-factor needed to topple his current Leeds side.
Leeds have won plenty of admirers on their return to the top flight this season for their fast and furious brand of football.
They have notched four wins and sit 14th before Friday's home game against West Ham, but Bielsa admits that in last week's defeat at Chelsea they were taught a valuable lesson.
"What we have to learn is something that is one of the most difficult things to learn in football," the former Argentina and Chile boss said.
💬 Marcelo on the season so far... pic.twitter.com/uWAQeNGgWr — Leeds United (@LUFC) December 9, 2020
"The big, big teams, when everything you do is not enough, they do what's necessary.
"When they find out everything they've done is not enough, they go above and beyond to make that difference."
Leeds were narrowly beaten in a seven-goal thriller at Liverpool on the opening day and produced a stirring fightback in early October to draw 1-1 against Manchester City at Elland Road.
"When a team does well it increases the responsibility upon them because as a team that played well, the rival will notice this and it will capture their attention," Bielsa said.
"This was reflected in the game against Chelsea because in this game Chelsea produced their best game in physical data.
"It's not they improved just a little bit, they increased about 20 per cent in all their physical aspects. For us, from a physical standpoint, we played our second-best game of the season.
"We were better than Chelsea from a physical point of view, but not in the proportion we had over them prior to the start of the game.
"For us to be better than a great rival, we need to make them worse. For this we need to obtain a clear physical advantage over our opponents and in this case, there is not a lot more we can demand from the players."
My debut finally came after so much time waiting to play my first game. Unfortunately, the result wasn't good and I'll have to stop due to some aches. I'll work, work and work to get well as soon as possible and get back stronger! #MOT pic.twitter.com/32euTQL5fw — Diego Llorente (@diego_2llorente) December 9, 2020
Bielsa also highlighted his side's frailty at set pieces, which West Ham will look to exploit at Elland Road, having been highly effective from them under David Moyes this season.
"We're trying to improve this aspect in all the ways that I can imagine are possible to improve it," Bielsa added.
"If up until this moment we haven't been able to resolve it, it shows I haven't yet found the tool which will prevent this from happening."
Bielsa's task on Friday has been made even harder by the absence of central defenders Robin Koch and Diego Llorente.
Koch will be out for around three months following knee surgery on Tuesday, while Llorente sustained another muscle strain during his belated debut at Chelsea.
