President Barack Obama welcomed David Cameron to the USA by taking the Prime Minister to watch his first game of basketball.
Mr Cameron admitted having difficulty following all the rules, but said the president was giving him some tips as they watched Mississippi Valley State University play Western Kentucky University in Dayton, Ohio.
The world leaders took front row seats for the opening game in the March Madness tournament, which saw Western Kentucky storm to a 59-56 victory in the final few minutes.
During a joint interview at half time, Mr Cameron said: "I'm enjoying it. It's fast, it's pretty fast and furious. It's hard to follow sometimes exactly who's done what wrong."
Asked if the president was helping him, Mr Cameron told CBS basketball correspondent and former pro player Clark Kellogg: "He's giving me some tips. He's going to help me fill out my bracket."
Mr Obama, a keen fan of the sport, replied: "And he's going to teach me cricket. Because I don't understand what's going on with that game."
Mr Cameron said he saw "a lot of similarities" between basketball and football, but admitted the American sport was "very fast".
On the first evening of his three-day visit to the US, he also talked of the excitement about the forthcoming Olympics in London, telling Kellogg: "We're going to be rolling out the red carpet to the whole world. Everything is on time, on budget, all the stadia are built, everything is ready to go.
"We're just ready to welcome a lot of people to London. My message to people is to come, come and visit, come and see the Olympics and come and stay."
The basketball contest, staged by the National Collegiate Athletic Association, pits teams from universities across the USA against one another and draws large TV audiences nationwide.
Dressed casually for the evening of sports, the two leaders were applauded loudly as they took their seats in the front row of the stands, just behind one of the hoops.
Mr Obama and Mr Cameron turned to chat to Dayton University students in the seats around them.
And as play progressed, the two leaders were often deep in conversation - basketball expert Mr Obama apparently pointing out aspects of the play to Mr Cameron, who admits he is a novice at the game.
During their televised interview, Mr Obama explained why he had chosen to bring the British leader to the event.
He said: "I thought it was going to be wonderful for the Prime Minister to have a chance not only to see a basketball game for the first time but also to come to the great state of Ohio because sometimes when we have foreign visitors they are only visiting the coasts."
The president added: "The heartland is what it's all about."
The Mississippi Valley State Delta Devils and Western Kentucky Hilltoppers were among the weaker sides in the March Madness tournament, taking part in a play-off to win the prize of a place in the first round proper.
College basketball is a huge draw in the US and the University of Dayton Arena was packed for the televised game, which was watched by 8,461 spectators.
As well as an enjoyable night out before getting down to serious business today, Mr Obama is certain to have calculated that footage of him at courtside will do him no harm in what will be a key swing state in November's presidential elections.
He looked relaxed as he took off his dark bomber jacket, rolled up his sleeves and leaned back in his seat alongside Mr Cameron.
As befits a spectator at a US sports event, the PM - dressed in blue polo shirt and dark jeans - tucked into a hot dog, washed down with Coke.
Beside him sat chief of staff Ed Llewellyn, while Mr Obama had White House chief of staff Jack Lew and Ohio governor John Kasich by his side.
The four-lane highway from the nearby Wright-Patterson Air Force Base, where the two leaders landed on Air Force One, was closed to other traffic as the presidential motorcade swept to the game.
At half-time, with Mississippi Valley enjoying a 23-19 lead, Mr Obama and Mr Cameron walked on to the court for their interview.
Students crowded around the president to have their photo taken, as Mr Cameron stood aside and let Mr Obama take the adulation.
Mr Cameron and Mr Obama were later taken back to Air Force One in a motorcade.