The Foxes host Pep Guardiola’s high-flying City on Tuesday, aiming to re-find their form after a surprise 3-0 Premier League defeat to Crystal Palace that ended an impressive run of results since the Frenchman took over at the club in October.
Puel’s Southampton lost the League Cup final 3-2 to Manchester United at Wembley when Saints’ striker Manolo Gabbiadini had a goal controversially ruled out with the game at 0-0.
Defeat was hard on Puel and Southampton and, now Foxes manager, he is eager to right some wrongs.
“The next game will tell us if this is possible or not because we have to play a fantastic team,” said Puel.
“They are the top team in Europe and it’s difficult to beat this team.”
Puel will be without the banned Wilfred Ndidi after he was sent off following two yellow cards — the second for diving — in Saturday’s defeat.
Robert Huth and Matty James are also out with ankle injuries for the Foxes, and Puel is likely to make changes after saying his players struggle to play two games in quick succession.
“It’s difficult to understand when we can play with this quality against Southampton (a 4-1 win three days before losing at Palace) and the game afterwards is so difficult,” he said.
“It’s difficult to play every three days with the same intensity and concentration. Perhaps there’s a little tiredness for the players. It’s important to analyse enough to look forward.
“We can do something against Manchester City, this is the most important thing. For the future it will be important to have some rotation and changes without losing the quality.”
The other quarter-final tie on Tuesday sees Arsenal taking on West Ham. On Wednesday, Bristol City host Manchester United while Chelsea take on Bournemouth.