‘Del Boy’ was clearly the more skilful of the two and had enough resistance to keep Johnson from picking up many rounds in the fight to record a 118-109 (twice), 118-110 victory on the judges scorecards.
The 30 year-old is now set for high-profile return with Fury after the former Irish champion laboured to a fourth round stoppage win over Joey Abell in chief support.
Fury, 25, came in at a career-high weight of 277lbs on Friday, and the extra weight obviously restricted his movement – although did not affect his punch-power, which overwhelmed the American.
In a scrappy and sometimes dirty contest, Fury put Abell on the floor four times, but did get buzzed himself en route to recording his 16th KO from 22 outings.
On the undercard, Hughie Fury halted Matt Greer in two rounds to take his record to 13-0 with an eighth stoppage, whilst Frank Buglioni took just five rounds to take out Gaetano Nespro.
Also on the bill, Bradley Skeete and Thomas Stalker carded points wins over Christopher Sebire and Dan Carr respectively to round off an entertaining card in London.
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