Andy Murray’s Florida training proved invaluable as the British hope handled the heat to progress to the second round of the Australian Open on Tuesday. The world number four, with new coach Ivan Lendl in his corner, bounced back from losing the opening set to oust American Ryan Harrison in four sets in searing on-court temperatures. Murray, 24, twice a beaten finalist in Melbourne, eliminated the 77th-ranked Harrison 4-6, 6-3, 6-4, 6-2 in 3hr 12min on Hisense Arena. The Scot uses his Florida base to work on his fitness ahead of every new season and he adapted well to the sweltering conditions that have greeted the year’s opening grand slam tournament this week.