NFL: Raiders' Antonio Brown suffers 'frostbitten feet'

Antonio Brown spent eight seasons at Pittsburgh Steelers before joining Oakland Raiders in March

If you move to California the last thing you expect to suffer from is frostbite - but try telling that to NFL star Antonio Brown.

The Oakland Raiders wide receiver has been missing from training in recent weeks with a mysterious foot injury.

NFL.com cite sources that say Brown is suffering from extreme frostbite caused by entering a cryotherapy chamber without wearing proper footwear.

Raiders coach Jon Gruden said he is "gathering information" about the injury but could not say when Brown would return to action.

Whole body cryotherapy is a treatment that involves exposure to extremely cold temperatures for several minutes with the hope of aiding muscle repair and speeding up recovery from injury.

Individuals using a cryotherapy chamber wear minimal clothing but the feet, hands, ears, mouth and nose need to be covered to minimise the risk of a cold-related injury.

NFL reporter Ian Rapoport says Brown has visited a foot specialist about the issue and is being monitored "day to day".

Brown posted a gruesome photo on his Instagram account last week showing the soles of his feet blistering and peeling.

The 31-year-old became one of the highest-paid wide receivers in the NFL when he joined Oakland from Pittsburgh Steelers in March on a three-year deal worth more than $50m (£41m) per season.

The Raiders host Denver Broncos in their NFL season opener on Monday, 9 September.