Trailing 3-1 at one stage in the afternoon session, Robertson had rallied to lead an open and free-scoring match 5-3 after the opening session.
The contest's conclusion would prove far more arduous, with the average frame time doubling in the final session, but the Australian outlasted his fellow 30-year-old to make the fledgling event's finale.
Robertson made Murphy wait for close to an hour to finally sink his first pot of the match, but after the Australian's 76 break sealed the opening frame, Murphy managed to get off and running and build some momentum.
'The Magician' came in with a run to 61 to win the second after Robertson had let his opponent in following an initial 23 break, and a tense third frame also went the way of the Englishman after a series of tense exchanges and a Robertson unforced error that allowed Murphy to sweep in with a late 37 to steal.
Murphy continued to improve at the table and a meticulous 73 sealed a two-frame advantage heading into the first mid-session interval.
Robertson re-emerged in top form, however, racking up 222 unanswered points to level the match at 3-3.
First, Robertson made a monster 142 clearance to move top of the tournament break-building charts and claim pole position for the £2,000 bonus on offer. A 69 break in the sixth then restored parity.
Further big knocks of 87 and 68 completed a 400+ point half-session for the Melbourne left-hander and left him with a two-frame lead of his own at the conclusion of the opening session.
The evening's play in China would prove to be a stark contrast, however, with the two invariably locked in a series of stalemates and scrappy exchanges.
Murphy closed to within a frame as the session opened before Robertson's 91 break - the only significant break of the session - saw him regain his two-frame advantage at 6-4.
Murphy stole the next on the colours for 6-5 after half an hour littered with baulk duels and nervy misses, but it would be his last frame of the tournament.
Robertson edged the next three equally scrappy frames to secure victory, with the Englishman guilty of a number of inexplicably loose plays which allowed his opponent to capitalise.
As he had en route to victory at the 2012 Masters, Robertson defeated Murphy by four frames and will now look to add to his trophy cabinet by overcoming the man he beat in the last four at Alexandra Palace - and new world number one - Trump, who thrashed Peter Ebdon 9-1 on Friday in the first semi.