The 25-year-old Hackney man was fortunate to preserve his unbeaten record as he repeatedly tested the patience of the referee Victor Loughlin on the way to an underwhelming victory with scores of 116-110, 114-112 and 114-113.
Okolie had made a smooth start in the opening round, pumping out stiff jabs, and digging spiteful shots into the ribs of Askin
The long limbs of the Londoner were posing early problems for Askin, who only managed to land a solitary hook up close as both fighters mauled through the second round.
Both men continued to wrestle in a messy third, with ring official Loughlin issuing words of warning, and Okolie did briefly clean up his work in the fourth, unloading a few stiff right hands.
But Loughlin had seen enough by the fifth, taking a point from Okolie for reckless use of the head, and Askin was then bundled to the canvas.
The Blackpool man tried to ignite this scrappy encounter in the sixth as he marched forward to deliver right hooks, only to be ticked off by the exasperated official for a low blow.
A booming straight right hand from Okolie drew gasps from the crowd in the seventh, but he was docked another point for holding in the eighth.
Despite the deductions, Okolie did appear to be edging the fight with marginally cleaner work, while the increasingly frustrated Askin was still struggling to unravel his opponent’s awkward style.
A third point was taken from Okolie in the 11th by Loughlin for persistent holding, and he would have been relieved not to lose another before the final bell.
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