Lee Selby overcame a second round knockdown to retain his IBF featherweight belt with a wide points victory.
The Welshman recovered well after being dropped heavily and benefited from a point deduction for Hunter as he racked up winning points tallies of 115-111 116-110 and 116-110 at The O2.
Selby took the centre of the ring in the opening round and stabbed out punches as Hunter spent much of the three minutes on the back foot.
But Hunter exploded into life in the second, uncorking a big left hook that sent Selby crashing onto his back.
Rising quickly from the canvas, Selby had been dropped for the first time in his professional career, ending any lingering thoughts of a routine title defence.
The Barry man tried to find his feet in the third and landed a crisp right hand before spinning neatly out of range.
Selby seemed to be settling into his rhythm and started the fourth with another swift right, although Hunter gave a further glimpse of his threat when he countered with that dangerous hook.
But the steady work-rate was coming from Selby, who rattled in that accurate right in the fifth, and Hunter shook his head after being tagged by more sharp shots in the sixth.
Hunter, nicknamed 'The Outlaw', had been disqualified twice previously and was ticked off by referee Marcus McDonnell after a low blow in the seventh.
This illegal shot drew a fiery response from Selby, with both men trading big hooks, and Hunter appeared to be troubled by a left hand.
With the fight drifting away, Hunter fought with more desperation in the eighth and his punches again drifted below the belt line, receiving a point deduction from McDonnell.
Despite this punishment, Hunter strayed low once more to receive a final warning in the ninth, while Selby watched on with his usual calmness.
In the closing rounds, Hunter unloaded more hooks, seeking another telling punch to change his fortunes, but Selby was satisfied with his points tally and skipped neatly away from danger.