Kell Brook will defend his IBF welterweight title against Errol Spence Jr, promoter Eddie Hearn has confirmed.
Hearn had been examining all options for Sheffield fighter Brook, including a superfight showdown with fellow Brit Amir Khan.
Moving up in weight class was also a possibility, which would have seen him relinquish the IBF belt.
But he has elected to defend his crown against mandatory Spence Jr, unbeaten in 21 fights.
Matchroom Boxing chief Hearn confirmed on Monday night that the fight had been agreed, stating it would definitely be in the UK.
Reports suggest it will take place on May 20 in Sheffield - though Hearn attempted to pour water on speculation on Twitter.
But it appears highly likely the fight will he held at Bramall Lane.
Sheffield United supporter Brook has previously stated his desire to fight in S2 and Hearn has long planned to make it a reality.
Challenger Spence Jr has stopped 18 of his 21 opponents. The 27-year-old knocked out Leonard Bundu to earn a shot at Brook's world title.
Brook has been out of action since September after fracturing his eye socket in defeat to Gennady Golovkin in a middleweight world title contest.