World number two Murray, playing his first match since the Australian Open final, outclassed Taro Daniel 6-1 6-3 6-1 to the delight of a boisterous home crowd in Birmingham.
Japan later hit back with world number six Kei Nishikori beating local favourite Dan Evans 6-3 7-5 7-6(3), meaning Saturday's doubles rubber could be pivotal.
Daniel, ranked 87th in the world, briefly knocked Murray out of his stride to break early in the second set but he was no match for the man who led Britain to their first title since 1936 virtually single-handed last November.
"I was getting a little out of breath, but I played a good match and served well," Murray said. "I had unbelievable support today and it was great to play in front of a full house."
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Murray, who won 11 live rubbers in last season's march to the title, could team up with brother Jamie on Saturday, although captain Leon Smith could use doubles specialist Dominic Inglot and rest him for Sunday's clash with Nishikori.
(Reporting by Martyn Herman; Editing by Janet Lawrence and Ken Ferris)
