Nkunku joined the Blues in the summer from German side RB Leipzig. He quickly assimilated into the Chelsea squad and impressed during our pre-season tour of the United States.

However, in our final friendly of that trip against Borussia Dortmund, Nkunku suffered a knee injury. He would be ruled out for more than four months.

Nkunku's journey back to the first-team squad involved countless hours of unseen rehabilitation and recovery work a Cobham. He returned to the matchday squad on Saturday against Sheffield United but was an unused substitute.

It was a different story for Newcastle's visit to Stamford Bridge. With just over 20 minutes remaining, the Frenchman was called back from his warm-up by Jesus Perez. It was time for Nkunku to make his Chelsea debut.

In his first appearance, Nkunku's quality was evident. That he stepped up to take a penalty in the shootout – and dispatch his effort with complete conviction – is a testament to his character.

It was a positive start for the Frenchman in blue. Yet as Pochettino highlighted after we secured our place in the Carabao Cup semi-finals, it is not the right moment to judge the impact Nkunku will have at Stamford Bridge.

'We are talking about a player who arrived and suffered an injury,' explained Pochettino. 'Now, he meets the team and Premier League in the middle of the competition. Time is needed to start to perform and to get the best form.

'Anyone can judge [a player] straight away, but the most important is in which form. The expectation is to see the best Nkunku, but the problem is we need time for him to perform in the way we expect.

'It is one thing is to be available; another is to perform in the way we expect. That is why we are not going to put too much pressure on him. Day by day we will push him to arrive at his best as soon as possible.'