British Olympian Lawrence Okoye, who impressed NFL scouts with his rare physical ability, will sign with the 49ers as an undrafted free agent, he announced on his Twitter page.

Okoye will sign a three-year contract with the 49ers and attempt to make a transition to defensive line in the NFL.

Coach Jim Harbaugh, speaking Saturday evening after the draft, that he felt "inadequate" when he met the 6-foot-6, 305-pound Okoye on a recent visit to the 49ers' team offices.

"This is an Adonis, a great physical specimen of a man," Harbaugh said. "Our creator created a beautiful man."

Okoye, 21, was an accomplished rugby player who decided to begin throwing the discus. Two years later, he became the British discus record-holder and placed 12th in the London Olympics.

He has never played football, but Harbaugh said giving him a chance to learn from defensive line coach Jim Tomsula may enable him to become a top-level football player, too.

"You start to put the pieces together and say, 'Taking on football at this time in his life, I can see this guy doing it,'" Harbaugh said. "I'm excited."