Sports briefly: Heavyweight champ Tyson Fury retires, then takes it back

Three hours after declaring he had retired, troubled world heavyweight champion Tyson Fury took to Twitter again on Monday to announce: "I'm here to stay."

The contradictory tweets came almost two weeks after the British fighter called off his title rematch against Wladimir Klitschko for a second time, his handlers saying he was "medically unfit." Fury had earlier been charged by the U.K. Anti-Doping agency over a positive test.

Fury hasn't fought since beating Klitschko in November 2015 to claim the WBA, WBO and IBF titles.

In a tweet Monday morning, Fury wrote: "Boxing is the saddest thing I ever took part in. I'm the greatest, & I'm also retired."

As news of Fury's apparent retirement spread, he returned to Twitter on Monday afternoon.

"Hahahaha u think you will get rid of the GYPSYKING that easy!!!" Fury said, referring to his nickname. "I'm here to stay. [hash]TheGreatest just shows u what the Medea are like. Tut tut."

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