Lascelles and his team-mates are in Nanjing, China, for Wednesday’s fixture against Wolverhampton Wanderers.
The team is being coached by Ben Dawson and Neil Redfearn following the departure of Rafa Benitez last month.
Talks are ongoing with Sheffield Wednesday over a move for Steve Bruce, who owner Mike Ashley wants to succeed Benitez at St James’s Park.
United captain Lascelles told NUFC TV: “We can’t dwell on us not having a manager yet. You’d rather know than not know, but, again, we can’t control it. It’s my job, and the job a few of the other boys, to make sure everyone’s on it so whenever a manager does come in, we’re ready for whatever instructions he decides to give us.”
Newcastle United to ‘push ahead’ with £48m double raid, Toon in ‘pole position’ for £42m Tottenham star
Newcastle United 'closing in' on £13m striker following St James's Park visit
Newcastle United in ‘pole position’ for Tottenham Hotspur ace as Magpies ‘eye’ Chelsea quartet
Jamie Carragher delivers mixed verdict on Newcastle United's £60m transfer window spend
Major injury blow puts Newcastle United contract on hold as Eddie Howe considers options
Newcastle will train twice today in the heat and humidity of a Chinese summer.
“It’s really hot, and it’s quite humid as well,” said 25-year-old Lascelles, who took the captain’s armband three years ago. “Other than that, football’s the same. It’s about getting used to the pitches. Some of the lads are a bit jet-lagged. We’re all happy. We’ve had a good session.
“Wherever we are, we’ll always do our best, whatever the circumstances are. As professionals, that’s all we can do. Ben’s putting on some good sessions for us.”
Meanwhile, Manchester City, also competing in the tournament, will arrive late in China are having their flight to Shanghai cancelled twice.