Trump survived an epic fightback from Mark Williams to clinch victory in a deciding frame, while O’Sullivan duly completed a 17-11 win over John Higgins to become, at 46, the oldest player to reach a Crucible final since Ray Reardon in 1982.
As well as a record-equalling seventh world title for O’Sullivan or a second for Trump, plus a £500,000 first prize, the world number one ranking will also be at stake over four sessions which conclude on Monday evening.
Trump, who won the title in 2019, said: “It’s always been a dream of mine to play Ronnie in the final. There have been times I didn’t think it would happen, but now it’s here.
“Ronnie was a hero of mine growing up, and he’s already the best player that’s ever lived, but I think he wants to confirm it by winning a seventh title. He tries to play it down, but I think he’s more determined than ever.
“In the past he could lose his head or play absolutely shocking, but now he is so consistent, he doesn’t play any rash shots. I don’t think I can get away with playing at the level I have so far in this tournament to have a chance.”
Trump had seen a 12-5 advantage evaporate against Williams, who clawed his way back to lead 16-15 and move one frame away from what would have been the greatest semi-final recovery in Crucible history, and second only to the nine-frame deficit recovered by Dennis Taylor in the 1985 final.
But having fallen behind for the first time, Tramp rallied to haul level then produced two outrageous cross-doubles in the course of clinching a tension-filled decider, before which both players had received a raucous standing ovation.
“I just tried to stay positive,” added Trump. “I was still enjoying it and there was nothing really I could do – my long shots weren’t going in but I had no other shot so I had to keep going for them.
“This feels like a free shot because I wasn’t expecting anything of myself. I feel like I’m getting closer to the feeling I had [in the 2019 final]. I feel like my best is close now, and I’m feeling positive.”
It proved scant solace for Williams that his four centuries in the match took his tally for the tournament to 16, equalling Stephen Hendry’s single-year mark from 2002, but he rued his inability to maintain a streak that at one stage had seen him win nine of 11 frames.
He joked: “I’d rather have lost 17-1 and been home yesterday. I put so much pressure on him that he was gone. At one stage I don’t think he potted a ball for 45 or 50 minutes, and who ever does that to Judd Trump?”
O’Sullivan had effectively ended his semi-final as a contest after winning five of the eight frames in the morning session against Higgins to move two from victory at 15-9.
But despite firing three centuries, O’Sullivan had been clinical rather than vintage as he mopped up after a succession of mistakes by Higgins, the Scot showing his frustration by slamming his cue into the floor when he let his opponent in early in the 22nd frame.
O’Sullivan did his best to prolong the inevitable, gifting Higgins two of the first three frames upon their resumption before a break of 83 belatedly got him over the line.