This tournament hasn't been kind to the home favourite over the years, and his run to the quarter-finals in 2016 was the best he had previously managed since the event's inception.
However, Allen has been a different proposition this week and knuckled down well when Walden won two frames on the bounce to draw level at 2-2, winning a lengthy frame six before finishing the job with a typically silky run of 73.
Allen immediately looked comfortable when moving into a 2-0 lead, but Walden hit back with breaks of 73 and 80 to suggest the match might go all the way.
To his credit, Allen regained control when dominating the fifth frame and although frame six took him 52 minutes to win, it proved to be a crucial one as he ran with that momentum and followed up with a brilliant 133 to put himself on the cusp of victory.
A determined hand of 59 kept Walden's hopes alive, but Allen was unwilling to let his grasp on the contest slip and he closed out the match in ruthless fashion.
Allen said afterwards: "It wasn't pretty at times – I was a bit tentative out there.
"I knew what a big occasion it was, but I tried to loosen myself up after the interval, went for a few more shots and tried to pick up the pace a little.
"Ricky is very tough and he plays a lot of clever shots. We have a very similar style of game.
"I've a big final to look forward to – I'm not entirely worried about who I have to play.
"If I had to pick I would probably pick John [Higgins]. To play one of the all time greats in the final here in Belfast would be a dream come true."
Allen will indeed face John Higgins on Sunday after the veteran Scot trounced Yan Bingtao 6-2.
Bingtao made the early running to lead 2-0, but Higgins produced a stunning display thereafter as he reeled off six frames in succession with breaks of 52, 83, 61, 78, 75 and 90.
