The Blues put on a dominating display against League Two side Barrow at Stamford Bridge on Tuesday night, securing a convincing victory in front of their fans to advance to the fourth round of the Carabao Cup.
Nkunku, making his first start for Chelsea since the opening-day defeat to Manchester City, scored twice inside 15 minutes as Barrow struggle to contain their Premier League opponents.
A Joao Felix free-kick then hit the post and bounced in off Barrow goalkeeper Paul Farman to put Chelsea 3-0 up at half time.
It looked as though Chelsea could rack up the goals when Pedro Neto scored his first for the club straight after the interval, but Barrow restricted the hosts to just one more goal from then on, Nkunku completing his hat-trick in the 75th minute.
Maresca was pleased with his team’s professional and dynamic performance against Barrow and said three stars from the victory ‘deserve to start’ in the Premier League.
‘I’m happy. Happy for Pedro [Neto], happy for Christo [Nkunku] and for Joao [Felix], for all of them,’ Maresca said.
‘They all deserve to play from the start in the Premier League but they are not playing in this moment. But the way they take the chances when we give them minutes is fantastic.
‘No matter if it’s five minutes, 45 minutes or 90 minutes, they are all ready and this is the most important thing.’
Nkunku faces severe competition at Chelsea with £32m signing Nicolas Jackson enjoying an impressive start to the season, scoring four goals in five Premier League games.
But Maresca has suggested he could utilise Nkunku alongside Jackson as the season goes on.
‘That could happen,’ the Italian added. ‘But the problem is the defensive balance.
‘We can think to place with Nicolas, Christo, Joao, Cole Palmer, Noni, fantastic! But then who is defending? Me and you?
‘I would like to put all of them in because I really like football and I really like to keep the ball but the problem is when you lose the ball and then you have to defend. Not all of them can defend at the same level.’
Chelsea, who are currently fifth in the Premier League, return to domestic action on Saturday with a home match against Brighton.
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