He's the 6ft 6in, 21-stone Olympic discus thrower with a place to study law at Oxford University. But Lawrence Okoye's next career break came right out of left field.

The 21-year-old star from Croydon has signed for American football side the San Francisco 49ers.

Okoye, who came 12th in the discus event for Team GB at the London 2012 games, revealed on Twitter he would be going to San Francisco as an undrafted free agent.

He wrote: "Proud to announce that I will be signing with the San Francisco @49ers!"

Okoye, who has previously turned down offers to play rugby union, initially said he intended to carry on with the discus, and had set his sights on the Rio 2016 games.

But despite missing out on selection on the final day of the NFL draft, Okoye said he received interest from teams numbering "in the double figures".

He was snapped up by the Niners after impressing scouts at the Super Regional Combine, and will sign a three-year deal to play in the defensive line.

Okoye broke the British record for discus in his first year as a senior athlete in 2011, and went on to win the European Under 23 title before competing at the London games.

Okoye said he had been a fan of American football since since his boyhood, and continued to watch televised coverage.

"It's something I've had in the back of my head for a long time so I decided to go for it," he told the Croydon Advertiser. "If I don't do it now I'm never going to do it, so it's something I want to prove to myself more than anything."

But having made his move, the rookie will now have his work cut out for him. For he has yet to play a full game in his life.

"Obviously I've got no experience playing football so it's going to be one hell of a draft," he said before his selection.

"Discus is all about producing power from the ground up and that's what football is all about. I just got to make sure I keep working hard every day."