Newcastle United won 3-1 against Southampton at St. James’ Park at the weekend.
Newcastle won 3-1 against Southampton at the weekend, but Lascelles felt he could have done more to stop Mario Lemina’s strike.
And Lascelles is not expecting to get away with making a mistake, even though Newcastle picked up the three points.
The £40,000-a-week defender (Sportac) said: “I should have done better with that [Lemina’s] goal, it shouldn’t have even been a cross.
“So I will be sat down in his office and he will be grilling me about that like we lost the game. But that’s him for you and, as players, we all appreciate that.”
Newcastle’s victory over Southampton has ensured their safety in the top flight for another season.
The Magpies put in an excellent display in the contest, with Ayoze Perez scoring a hat-trick.
Newcastle have been in fine form at St. James’ Park over the latter part of the season, which has elevated them up into 13th place in the Premier League.
Newcastle are next in action on Saturday when they take on Brighton & Hove Albion at the AMEX Stadium.