It was also a chance to engage in a little sports diplomacy in support of New Zealand's bid to gain a seat on the Security Council for two years.
Key welcomed Sir Richard to the event saying they had connection of sorts. His wife's parents had once worked in shoe factory and as a result she got a holiday job at a shoe company, O'Brien's in Christchurch, including putting the screws into the studded boots that bowlers wear.
And Sir Richard had been a special client of the factory.
"On her tax return each year, when they used to ask her to put down her occupation, she would put 'stud screwer.'
The people in the office would ask her to put 'factory worker" instead, Key said.
"I used to encourage her to put 'stud screwer' down for very different reasons.
"That's far too much information but [it's] a link between our two families Sir Richard that you never knew was there."
The diplomats didn't seem to mind. Among them were diplomats from Jamaica Palestine, Tunisia, Sri Lanka, Indonesia, Afghanistan and most either took to the mini pitch with Key and Sir Richard or had their photo taken with them.
McCully eventually took the bat and was stumped by the Prime Minister playing wicket keeper.
Sir Richard said he had taken part in Cricket World Cups in 1975, 1979 and 1983.
The 10 ICC countries qualified for the cup automatically and 96 associate or affiliates tried to make the final 14.
The four others that made it were Ireland, Scotland, United Arab Emirate and Afghanistan had all secured a place. Each would get a chance to play the other teams.
He said Afghanistan's participation was a remarkable story "for obvious reasons."
"Some years ago when the Under 19 Cricket World Cup was held in New Zealand, I did have the privilege of speaking to the Afghan Under 19 team in Christchurch, offering some words of encouragement and I suspect some of those same players now will get an opportunity to play against the best in the world in 2015."