Robert Helenius - who fought Anthony Joshua earlier this month - has failed a drugs test that was taken the day before their heavyweight fight.

The Finn only agreed to face Joshua at the O2 Arena at short notice, a consequence of previous opponent Dillian Whyte also returning an "adverse analytical finding".

Joshua was able to brutally knock out Helenius in the seventh round, the highlight-reel stoppage being required after an uneventful first half of the contest.

However, attention will now turn to the latest failed drugs test in boxing, with Helenius having tested positive for a currently-unknown banned substance.

Helenius had been competing in his second fight in the space of a week, with the test in question coming six days after he had stopped compatriot Mika Mielonen.

VADA (Voluntary Anti-Doping Assoication) testing was not used for the encounter in his homeland, and is generally only involved for high-profile bouts due to the cost involved.

While the failed test will have little baring on Joshua due to his win, it puts a further black mark on the sport with women's super-featherweight world champion Alycia Baumgardner also returning an "adverse analytical finding" after her recent world title bout.