Career
Blackwell turned professional on 26 June 2009, having had no amateur experience and spending his teenage years in the sport as a white-collar boxer. On 18 June 2011, Blackwell challenged Martin Murray for his Commonwealth middleweight title, as well as the vacant British middleweight title. Murray handed Blackwell his first career defeat when the latter was pulled out by his corner at the end of round five.
A successful defence of the English middleweight title came on 3 March 2012, with Blackwell stopping Martin Concepcion in four rounds.
This turned out to be a tough outing for Saunders, as Blackwell forced him to go the full twelve rounds. Blackwell travelled to Ukraine on 21 September 2013 to fight for the vacant WBA Continental middleweight title, but lost a twelve-round unanimous decision to Max Bursak.
During the fight, Blackwell scored a knockdown in the fourth round, and the result was seen by some observers as controversial. Having begun training with former middleweight world title challenger Gary Lockett, Blackwell made a third attempt at the vacant British title on 30 May 2015 against John Ryder.
Two successful title defences were made in the remainder of 2015, against Damon Jones on 25 July (sixth-round stoppage), and Jack Arnfield on 14 November (unanimous decision).
During the tenth round the referee summoned the ringside doctor to assess Blackwell, who in turn deemed him unable to continue due to the swelling on his head obstructing his vision, therefore handing Eubank Junior. the victory and title. Some minutes after the fight was stopped, Blackwell was given oxygen and taken out of the arena by stretcher. He was later hospitalised with bleeding of the brain, and is currently in an induced coma, but an operation was not deemed necessary.