Given the busy nature of England’s schedule, McCullum confirmed he will miss some series and hand responsibility to his assistant coaches. He also said there will be times when he tours with his family, who live in New Zealand.
England have won all five Tests they have played this summer and will aim for a six-match clean sweep this week.
They have not won all Tests in a home summer since they earned seven wins in 2004.
England will give a debut to Leicestershire left-arm pace bowler Josh Hull, despite the 20-year-old averaging almost 63 in his 10 first-class matches.
At 6ft 7in, with the ability to bowl a lively pace and swing the ball, Hull is the latest in a line of players picked by England on their attributes and potential rather than domestic record.
“We need to identify that county cricket and Test cricket are slightly different games,” said McCullum.
“What we are trying to achieve is bringing in some of these guys who we see as rough diamonds with incredibly high ceilings.
“We look at these guys and say ‘we think they will be good’. It might take time but we think they are worth investing in.
“Josh Hull is 6ft foot heaps, bowls left-arm, ranges in pace from 80 to 90mph, swings it not too dissimilar to the likes of Jimmy Anderson. He’s 20 years of age, from good farming stock. It’s not a huge gamble, is it?”
McCullum also said England “don’t know” the schedule of their three Tests in Pakistan, despite the tour starting in little more than a month.
The matches in October were due to be played in Rawalpindi, Karachi and Multan but may be moved because of refurbishment work before the Champions Trophy in Pakistan. Abu Dhabi could host part of the series.
“We can’t pick a team until we know where we’re going to play,” said McCullum. “It would be nice if over the next couple of days we found out.”
The forecast for the final Test against Sri Lanka is mixed and there was heavy rain in south London on Thursday afternoon.
The tourists have made two changes to their side and opted for four frontline seamers, with Vishwa Fernando replacing spinner Prabath Jayasuriya, while opener Nishan Madushka drops out and Kusal Mendis returns.
“It is disappointing when you lose,” said Sri Lanka captain Dhanajaya de Silva. “We need to do simple things right, put the balls in the right areas and play the patient game when we are batting.”
London [UK], : Former cricketer Courtney Winfield-Hill will join the England Women coaching set-up as an assistant coach for the upcoming tour to South Afric
Former cricketer and rugby league player Courtney Winfield-Hill has been named as an assistant coach for England Women’s tour of
Australian-born Courtney Winfield-Hill will join England's coaching team this winter for the tour of South Africa and Women's Ashes down under.Winfield-Hill pla
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