Anthony Joshua will fight Robert Helenius on short notice tonight, after the Briton’s rematch with Dillian Whyte collapsed due to an adverse drug-test finding. Joshua knocked out Whyte in 2015, avenging an amateur loss to his compatriot, and the old rivals were due to square off again this week. However, Whyte failed an anti-doping test, causing the bout to be called off. Now in comes Helenius, saving the weekend’s event as the Finn competes for the second time in seven days. Helenius, 39, beat Mika Mielonen in the third round last week, in what might have been a useful warm-up for his clash with “AJ”. • Get all the latest boxing betting sites offers Meanwhile, 33-year-old Joshua last fought in April, beating Jermaine Franklin on points to bounce back from two straight losses to Oleksandr Usyk. Joshua’s rematch with Whyte was meant to be the next step on the road to a fight with Deontay Wilder, and that contest is still in the works for early 2024. Here’s all you need to know. We may earn commission from some of the links in this article, but we never allow this to influence our content. This revenue helps to fund journalism across The Independent. When is it? Joshua vs Helenius will take place on Saturday 12 August at the O2 Arena in London. The main card is due to begin at 7pm BST (11am PT, 1pm CT, 2pm ET). Ring walks for the main event are then expected at around 10pm BST (2pm PT, 4pm CT, 5pm ET). How can I watch it? The event will stream live on Dazn. A subscription to the streaming platform is available to purchase here, with monthly plans starting at £9.99. Odds Joshua – 1/18 Helenius – 25/1 Draw – 17/2 Full odds via Betfair. Full card (subject to change) Anthony Joshua vs Robert Helenius (heavyweight) Filip Hrgovic vs Demsey McKean (heavyweight) Johnny Fisher vs Harry Armstrong (heavyweight) Derek Chisora vs Gerald Washington (heavyweight) Campbell Hatton vs Tom Ansell (super-lightweight) George Liddard vs Bas Oosterweghel (middleweight) Brandon Scott vs Louis Norman (featherweight) Maisey Rose Courtney vs Gemma Ruegg (super-flyweight) Click here to subscribe to The Independent’s Sport YouTube channel for all the latest sports videos. Read More Anthony Joshua to face Robert Helenius after Dillian Whyte fight cancelled Robert Helenius: Record of Finnish star stepping up to face Anthony Joshua Dillian Whyte vows to prove his innocence after doping test ‘adverse finding’ Who is fighting on the Joshua vs Helenius undercard tonight? How to watch Joshua vs Helenius online and on TV tonight Anthony Joshua focused only on Robert Helenius amid Deontay Wilder speculation