West Ham United boss Sam Allardyce dropped in on The Sun's offices in central London on Thursday to surprise TV personality and Hammers fan James Corden as part of his guest editorship of the newspaper.

Corden took over the running of The Sun for a day in aid of Sport Relief as the charity gears up for its weekend of events, which last from Friday through to Sunday.

As well as interviewing Prime Minister David Cameron, Corden conducted a chat with the West Ham boss, which the Gavin and Stacey star initially thought would be by telephone, but turned into an in-person meeting.

Corden told whufc.com: "It was great to see Big Sam, I loved it and having a chat with him was the only thing I really insisted on for my guest editorship.

"Before I said I wanted to interview the Prime Minister I said I wanted to interview Big Sam, so I'm thrilled it all came together.

"It's all about finding different ways to spread a message and try to raise money, so in that respect I'm very honoured to be the first person to do such a thing. I really have enjoyed it, it has been really good fun."

Corden is a huge fan of Big Sam and has been delighted with the team's upturn in form since Christmas.

He continued: "It's great and I hope any West Ham fans that were calling for Sam's head [have taken notice]. I listened to countless phone-ins saying he has to go and the board and all things like that, but I genuinely have a core belief that we'll never get relegated as long as he's our manager.

"I hope a few of them come forward and apologise for how they've been and how some of them have been for his whole leadership.

"I think we're in a great place, the atmosphere in the team looks great. It seems we have a real team instead of disparate individuals. Our fully-fit first eleven can compete in the top half of the Premier League, when you think of the last few years and some of the managers we've had that's not always been the case."

With Manchester United visiting the Boleyn Ground on Saturday, Corden revealed that he hoped to be there to cheer the Hammers on.

He added: "It's an easy three points isn't it?! I was a bit worried when I watched them against Olympiacos and I do hope Ryan Giggs isn't playing, but if we can get away with a point that would be great.

"I hope to be at the Boleyn Ground to watch the game!"

Big Sam was delighted to play his part in the day and he explained how the meeting came about.

"It was set up by Sean Custis [Sun football writer], who rang me a while ago and said James is going to be editor of The Sun for a day and as he's a big West Ham fan, could I come in and play a little prank on him.

"I was round the corner doing an interview with James which he thought was just going to be on the phone, the line got cut off, he was getting pretty annoyed and I walked round and surprised him.

"It's always great to see him, he's doing a fantastic job for Sport Relief and hopefully it'll raise as much money this weekend as it has done for the last few years.

"Certainly the effort he's put in, giving up his time is a fantastic gesture so I was happy to be there to play a short part in it."

The Hammers have got behind Sport Relief this season by donning t-shirts to promote the charity event at last weekend's match against Stoke City and during their crossbar challenge for Sky Sports programme Soccer AM.

Click here for more information on Sport Relief.