After Brendon McCullum finished with Test cricket, he decided to get into the horse racing business. He had been dabbling for years, but had big ideas for expanding on it by building a public syndicate. The plan was to start off small but “grow to the point of purchasing some of the southern hemisphere’s most sought-after colts and fillies to attack the world’s biggest races” and turn his business into “a sexy, recognisable, funky name in the equine game”. Anyone who liked the pitch could buy in, and plenty did. At one point, McCullum had 18 horses in the stable and the best part of 100 investors.

Six years later McCullum is back in Test cricket, with another big idea. He wants to get England playing in such an entertaining way that everyone’s attention is drawn back towards the longest form at a time when interest in it is flagging.

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A lot of people say Test cricket is still “the pinnacle of the game”. McCullum, who gave up his job in the Indian Premier League to take this one on, is honest enough to admit that it won’t be for long unless it does a better job of selling itself to the public and the players. And just like with his syndicate, he’s hoping he will be able to persuade everyone else to buy in to his ideas about how to do it.

That includes Jos Buttler, who is just about the biggest English star in cricket at the minute after his feats in the IPL. Which doesn’t mean Buttler is about to walk back into the Test team. McCullum was part of the selection panel that picked Ben Foakes and Jonny Bairstow in the squad for these first two Tests against New Zealand, opening at Lord’s on Thursday. But McCullum is eager to make Test cricket feel so exciting that Buttler wants to be back in the mix. And not just Buttler. McCullum also mentions Moeen Ali, Adil Rashid and Liam Livingstone, “all guys have played international cricket before, who have been successful in the other forms of the game and who you’d think would be able to transition across”.

Never mind that Moeen actually retired from Test cricket last autumn (“Has he?” says McCullum with a smile – “We’ll see.”), that Rashid hasn’t played a first-class match since his last Test, in January 2019, or that Livingstone hasn’t even made his Test debut. All four of them have, to varying extents, ended up prioritising their T20 careers over Test cricket and now McCullum wants to change their minds. “If we’re playing an attractive brand of cricket and we’re successful and people are getting right behind what we’re doing, then that might pique a bit of the interest of some of those guys.

“I look at all of them and think there will be a time where they may get an opportunity if they’re invested enough. But we’ll see. The squad we’ve picked have got the opportunity first and foremost. But then if you’ve then got some of these other guys wanting to play, banging the door down with their own performances, then you’ve got a team who can dominate at the top.”

McCullum wonders if there were times when these players felt pushed away from Test cricket by the way they were managed. “There’s probably been a bit of hurt at times for those guys too, because they’ve been in the team at times and then out of the team at others.”

He puts a lot of store in loyalty. “That brings about a bit of confidence that you’re going to get an opportunity for a period of time. You need a bit of time to work out whether you’re any good at this level or not. Selection loyalty is very important to me. I’d rather give guys one more game than they probably feel they deserve themselves.”

He admits this may be wishful thinking. Rashid is 34, so is Moeen, Buttler has already played 57 Tests. Besides which, the schedule is so congested that it’s getting harder for players to switch formats. “But my mentality is that if they’re the best cricketers, then why not have a conversation and see where you get to? It doesn’t mean they are going to make the side, they might not even be interested, but let’s at least have the conversation.”

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McCullum comes from a team who succeeded by making the most of their small resources. He makes it sound as if he thinks England failed to get the best out of their much richer ones.

Likewise with Livingstone, who is 28, and at a point in his career where he could reasonably choose to specialise in white-ball cricket. “We need to have a conversation about what his appetite for Test cricket is. And if he is keen on playing, then how does he see himself getting into the side? Just because you’re a good cricketer, it doesn’t mean you automatically get selected.

“You’ve still got to earn the right to be able to do so. I don’t have any preconceived thoughts about whether he’s good enough or not, I just look at him and think he’s a very good cricketer, and think it’s worth having a conversation.”

The point is that if your star players aren’t interested in playing Test cricket, how long can you keep claiming it’s the best cricket?

So what happened to the horse racing syndicate? Well, McCullum is still in the business, but these days he just “buys them and races them with a few mates in New Zealand”. The syndicate didn’t work out quite like he hoped, and you wonder whether his time in English cricket is going to, either. But still, he and everyone else had a lot of fun along the way.