In a perfect world, sure. But there are two sides to this story. Think Pep, even he admits he only managed to do what he did with that Barcelona because of the players he had. Having such natural talents like Messi, Xavi and Iniesta at their peak is like starting a 2000m race being at 100m away from the finish line.
It goes without saying that any coach would need truly special players to win this much in 4 years in a league typically dominated by Real Madrid. Same is true of Zidane's CL titles. You can't do that with a bunch of nobodies or average players. Great players are a pre-condition for this kind of success to be had consistently. At the same time its hard to argue that any good coach would have won the same because plenty of great coaches have top squads but dont reach this kind of success consistently. Give these players to Sarri and he'd have won maybe the cope del rey and a super cup in 4 years
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He's not wrong but it's also down to him, I think we need to play with Bentancur in front of the defense and have Pjanic further up linking play behind Ronaldo and Dybala
If you want to see a key difference between Pep and Sarri it is this: players of various levels around the world and at multiple clubs buy into Pep's ideas and implement them and all speak fondly of how much they learned from him.
In comparison, this is now the second club where Sarri cant get through to the players. And Juve is not some toxic chelsea squad that cant handle pressure or hasnt won much before. Rather this is a super experienced group who have won Serie A and cups a million times, and are led by the biggest CL winner of all time. When players of that tenure, caliber and winning record, who have also fully bought into and implemented the ideas of Conte and Allegri successfully, don't buy into your ideas then something is wrong either with your ideas or how you sell these ideas to them.