Brendon McCullum has promised to take a “firm grip” on England’s off-field behaviour following controversies during their antipodean winter tours.England white-ball captain Harry Brook was embroiled in a physical confrontation with a nightclub bouncer in New Zealand, and later admitted lying about the details of the evening in order to protect his teammates. The story fed into accusations of a drinking culture among the England cricket team, with Test players pictured taking part in long sessions in the bars of Noosa during their mid-series break in the Ashes. Speaking in an interview to the ECB for the first time since England reached the semi-finals of the T20 World Cup in March, head coach McCullum accepted he needed to take steps to ensure the same mistakes were not repeated.“You’re bringing up young men, they’re in an environment where there is a lot of pressure, there’s lots of distractions,” McCullum said. “They’re young guys who are growing up on the world stage under the brightest lights and sometimes they’re going to make mistakes.“Ultimately your job as the leader of the organisation is to try to make sure that we aren’t making those mistakes because they’re not helpful. In an ideal world they would never happen. It’s not always an ideal world. We’re just going to make sure that we’re looking after these guys whilst also occasionally using a firm grip to ensure that we are not making those same mistakes again.”McCullum was speaking at England’s training base in Loughborough, having just arrived in the UK following some time off at home in New Zealand.Jacob Bethell batting in the Ashes (Robbie Stephenson/PA) (PA Wire)He spoke out to defend his decision to take a break since the World Cup, following criticism from pundits including former England captain Michael Vaughan, who suggested McCullum should have spent recent weeks watching the County Championship.“I’ve been able to have a little break after what was quite a demanding time,” McCullum said. “I’m very lucky that, when Keysey (England managing director Rob Key) offered me the full-time role with the white-ball teams as well as the Test one, he was very mindful of the fact there would be a lot of demands with the schedule and that I had a young family. There would be times when I needed to be at home.“I’ve been on the road for 25 years so I’m not unaccustomed to the demands of touring, but it is important at times to take your breaks, refresh a bit and get ready for an exciting summer ahead.“I watched quite a lot of the County Championship. The way it is these days, there’s a huge system behind the England’s men side that feeds information into us. It is almost impossible to be at every game now when you’re on the road for 10 months a year. I’ve been across most of the matches and I’ve seen a huge amount of talent in the English game.”McCullum added that there were medical reasons for his return to New Zealand. “I’m not after pity but there were a couple of operations I had to have back home which have been booked in for a long time, so it’s nice to tidy that up.”England begin their Test match summer against New Zealand at Lord’s on 4 June.England squad v New ZealandBen Stokes (captain), Rehan Ahmed, Gus Atkinson, Sonny Baker, Shoaib Bashir, Jacob ‌Bethell, Harry Brook, ​Ben Duckett, Matthew Fisher, Emilio ‌Gay, James Rew, Ollie Robinson, ​Joe Root, Jamie Smith, Josh Tongue.