Robert Helenius failed a pre-fight drugs test prior to his recent heavyweight fight with former world champion Anthony Joshua, it has been revealed.

The 39-year-old Finn, knocked out by Joshua in the seventh round at London’s O2 Arena on August 12, had stepped in as a late replacement for Dillian Whyte, who had failed a drugs test himself.

Fight promoter Matchroom Boxing confirmed in a statement on Twitter that Helenius had “returned an adverse analytical finding” after being voluntarily tested on August 11.

Matchroom Boxing said: “Today, the Voluntary Anti-Doping Association (VADA) has informed Matchroom and the British Boxing Board of Control that Robert Helenius has returned an adverse analytical finding as part of a random anti-doping protocol.

“Helenius was voluntarily tested on Friday, 11 August before the heavyweight fighter’s defeat by Anthony Joshua in London on Saturday, 12 August. The result was made known to Matchroom today.

“Matchroom defers to the relevant regulatory authorities on next steps. We vehemently continue to support voluntary anti-doping testing. We are committed to promoting a clean and fair sport for all athletes.”

Joshua had been scheduled to fight British rival Whyte at the O2 Arena on August 12 before the latter returned an adverse finding from a doping test.

Whyte later said he was “shocked and devastated” to learn of VADA’s findings and intended to prove his innocence.