The 26-year-old extended his unbeaten record to 25 fights with a dominant display against the former world title challenger, but had to settle for a majority decision victory.
Judge John Keane scored the fight a 114-114 draw but his fellow ringside judges favoured Warrington’s much cleaner work with 116-112 cards.
Warrington’s win was greeted by raucous acclaim from his home city fans, who had been earlier cheered Nicola Adams to a stoppage win in her second professional fight.
Amid a deafening atmosphere, Warrington acquitted himself well from the start, taking the first two rounds on work-rate alone in what promised to be tight and gruelling contest.
The doctor was called to take a close look at a lump on Martinez’s forehead at the start of the third, and the challenger responded by working to Warrington’s body with some degree of success.
But Warrington was still shading the exchanges with his cleaner and more powerful work, and he opened up again in the fourth with a good right which briefly seemed to sting Martinez.
A left late in the round reminded Warrington his opponent had no intention of going quietly, but as the bout reached the half-way mark the home favourite looked to be well in command on the cards.
Martinez was hampered by a cut from an apparent head clash midway through the eighth, although he had some of his better rounds in the later stages as he matched Warrington for work-rate.
Nevertheless there were some nervous moments when the scorecards were announced before Warrington could finally celebrate in front of his adoring – and relieved – fans.