Oliver Kahn is one of the greatest goalkeepers in football history.The often vocal German possessed a mentality like no other. He was a 'win at all costs' kind of guy, regularly shouting and lashing out at teammates in order to try and succeed.It was an attitude that paid off and earned him the nickname 'Der Titan'. Throughout his glittering career, Kahn won eight Bundesliga titles, six DFP-Pokals and one Champions League, before retiring from the game in 2008.Today, the Bayern Munich legend celebrates his 51st birthday and we've decided to relive one of greatest stories about the German icon.The tale hails from 'Tor!', a book on the history of German football. Kahn was asked to partake in a penalty shootout for charity against a group of nine-year-olds.For every penalty the youngsters scored, money was then given to charity.So what did Kahn decide to do? Save every single one of the penalties. Talk about a winning mentality...

The fact it wasn't even Kahn's own money on the line just adds to the sheer ridiculousness of the story.

But that's what happens when you put a man nicknamed 'Der Titan' and who regularly gave his own Bayern teammates the hairdryer treatment into that kind of situation.

Since his retirement, Kahn has attempted to explain his unique playing style, telling the Bundesliga's official website that "goalkeepers need an element of insanity".

"I often use my body language to show my team 'complete presence' – and to instil respect, or even better fear, in my opponents," Kahn explained. "Goalkeepers need an element of insanity. Who else would stand there and allow people to shoot balls at their face or stomach, and still think it's great?"

Khan in action with Bayern

Those poor nine-year-olds didn't stand a chance in that shootout, did they?