Chelsea head coach Enzo Maresca said his players were still trying to adjust to his playing style after losing 4-1 to Celtic in a pre-season friendly in Indiana on Saturday.

Christopher Nkunku’s 89th-minute penalty was the only consolation for the Premier League side, while goals from Matt O’Riley, Kyogo, Luis Palmer – following a Benoit Badiashile mistake – and Mickey Johnston provided Brendan Rodgers with a much happier afternoon.

“Off the ball we need to improve things,” Maresca said, after also having to defend his “risky style” following a 2-2 draw with Wrexham last Thursday – his first game in charge.

“You can see sometimes we confuse when we need to play short and when we need to play a little bit longer but that is part of the process.

“We maintained a high line but when the ball is not under pressure, you need to drop. We are still confusing some things on the ball and off the ball. It is normal in this moment when we are trying to do something new.”

Chelsea had 23 shots to Celtic’s 14 and almost two-thirds of the possession, but were again guilty of some sloppy defending, leading to O’Riley’s opener from a short corner, before two goals in the space of three second-half minutes sealed their fate.

Some carelessness from Badiashile presented Palma with Celtic’s third and then a simple ball over the top released Johnston, who made it 4-0. Nkunku scored from the spot late on following a foul on Raheem Sterling.

Despite two lacklustre results, Maresca finished by insisting his team would be ready for their Premier League opener against champions Manchester City on August 18, live on Sky Sports.

He can only hope for better when meeting Mexican side Club America in Atlanta on Wednesday.