ANTHONY JOSHUA has triggered the clause to take an automatic rematch with Andy Ruiz Jr.
Joshua suffered the first defeat of his career when he was stopped in the seventh round by Ruiz on Saturday night - one of the greatest upsets in boxing history.
But after talks with promoter Eddie Hearn and trainer Rob McCracken, AJ has opted to go straight back in against his conqueror in an attempt to win back the world heavyweight titles he lost.
Joshua, 29, had been hoping to make a major impact on his debut fight in America against unfancied late replacement Ruiz.
But instead, the unbeaten heavyweight looked a shadow of his usual self as he was floored four times before the referee stopped the fight in the seventh round.
It left the 2012 Olympic champion facing up to the fact he was no longer an invincible force and the main player in the heavyweight division.
RIGHT THE WRONG
Lucrative fights with WBC champion Deontay Wilder and former champ Tyson Fury were put on ice after his stunning demolition at the hands of the overweight Mexican.
And now Joshua is aiming to right the wrong as quickly as possible, by challenging to win back the WBA, WBO, IBF and IBO belts in either Novermber or December this year.
Promoter Hearn said: "After meetings with AJ, Rob McCracken and the management team in New York, we have today triggered the contracted rematch clause with Andy Ruiz Jr.
"The fight will take place in Nov/Dec at a venue to be confirmed shortly."
The swift decision to step back into the ring came after old rival Wilder claimed Joshua lacked the mental strength to go seeking a rematch.
It could net Ruiz a £10million pay-day as the reports the underdog will be handsomely rewarded for his stunning upset.
And it appears McCracken will remain part of Joshua's team despite calls from Lennox Lewis to axe the coach because he isn't good enough at the elite level.
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When the initial contracts were signed for the Ruiz fight, it was likely that any rematch would be held in the UK.
A home fight is still thought to be the most likely, depending on what venues are available at the time, as Hearn decides whether to stage it in an arena or stadium.
But there is still the chance it could be staged in America again - both because Ruiz may prefer that option and because Joshua may want a second shot at convincing the US public he is the real deal.