O'Sullivan was quick to downplay his title chances following his win over Hossein Vafaei on Thursday but, only 24 hours later, he produced a much improved showing in a convincing performance that got better as the match went on.
O'Sullivan told World Snooker Tour afterwards: "I’d rather lose in quarter and semi-finals and enjoy it than try to go deep and not enjoy it.
"Trophies mean nothing to me, I have got enough of them and nothing left to prove.
"I have been on this road trip of playing tournaments for four and a half weeks and my main aim at the start was not to crack up, and I haven’t.
"I feel as if I have really cruised through it. That was the main aim, lots of smiley faces and try to pick up a few ranking points along the way."
Despite the first four frames being shared, it was Robertson who initially looked the more assured as he compiled breaks of 70 and 106 in the second and fourth respectively.
However, O'Sullivan found his groove following the mid-session interval and took control of the match as Robertson failed to register a single point after they returned.
A typically silky run of 80 in frame five appeared to ignite O'Sullivan and he didn't look back thereafter, the six-time world champion following up with a flawless clearance of 112 to put him on the brink of the last four.
Sure enough, he raced over the winning line moments later with a break of 68, setting up a meeting with Bingham, who barely had to break sweat as he beat Stephen Maguire 5-1.
Bingham broke the back of the match when putting together breaks of 53, 105 and 95 to lead 4-0, before Maguire enjoyed his only moment of cheer when hitting back with a brilliant 139 in frame five.
That was as far as the comeback got, though, Bingham closing out the match in the following frame to cap a fine afternoon's work and confirm a Saturday appointment with O'Sullivan.
The winner will face Neil Robertson in Sunday’s final, after he beat Mark Selby 6-3 in Friday’s first semi-final.