Anthony Joshua will continue his quest to become a three-time heavyweight world champion when he takes on Otto Wallin later this month.
The Brit will lock horns with the accomplished southpaw on the same card as Deontay Wilder v Joseph Parker in Saudi Arabia on December 23.
The fight will be the sternest test yet on Joshua's comeback trail following comfortable victories against Jermaine Franklin and Robert Helenius.
As Wallin, who boasts a 26-1 record, is coming off the back of impressive wins over fighters including Murat Gassiev and Dominic Breazeale.
Additionally, he is a left hander like Oleksandr Usyk and along with the Ukrainian's speed and intelligence, Joshua looked incredibly uncomfortable against his stance.
The 34-year-old will take on Sweden's Otto Wallin (right) in the Saudi capital
Wallin dealt major damage to Tyson Fury in a 2019 unanimous decision loss, the only defeat on his record
Jarrell Miller believes Joshua may have made a mistake picking the Swede for his next clash
As a result, Jarrell Miller, who was due to fight Joshua in 2019 before testing positive for multiple banned substances, reckons the 34-year-old may have made a blunder in agreeing to face the Swede.
'I feel honestly that [Joshua] might have made a mistake with picking Otto Wallin,' the American told SecondsOut.
'Even though Otto Wallin is not a one-punch knockout kind of guy, he is durable, he comes to fight, he is not a quitter and it is going to be a tough fight for [Joshua]. I don't think that it is going to be easy, at all.
'The mental mind state that [Joshua]has, is he going to hold up?
'When he fights in the UK, he has a little more oomph in his step a little bit, but when he fights outside of the UK, we don't get the same fiery person, the playing ground is going to be a little bit more even out in Saudi.
'I wish all of the luck to Otto Wallin, I want to really be the one to knock out [Joshua], but may the best man win, it is what it is.'
Miller and Joshua have been engaged in a bitter feud ever since their ill-fated clash. The pair almost came to blows at the press conference event for 'Day of Reckoning', which will also include the American's fight with Daniel Dubois.