Having finished the regular season first and second respectively, the pair were once again in dominant form as the play-offs got under way.
Defending champions Wigan re-stated their case for another Grand Final appearance on Thursday as they ran in 10 tries to dismantle a sorry Giants side 57-4.
Josh Charnley scored a brace and second row Joel Tomkins crossed for his first try for the club since returning from rugby union, as the title favourites outclassed their opponents.
Paul Anderson's men were blown away in the first half and trailed 24-0 at the break, before Leroy Cudjoe went over early in the second half.
However, that proved only a brief moment of respite as Wigan's tempo continued, leaving Anderson scathing in his assessment of his side.
"It's embarrassing. We dipped our toe in the water and it was too cold for us," he said.
"I thought Wigan were ready to play, they were very slick and we weren't at the races. Wigan were physically too big and too strong. We turned it in if I'm being honest."
Saints also quickly killed off any chance of an upset against Castleford as the visitors were unable to get on the board in a 41-0 thrashing at Langtree Park on Friday.
Man-of-the-match James Roby - surprisingly omitted from the Super League team of the season - scored twice in a seven-try masterclass from the hosts to keep Saints on course for a first Grand Final appearance in three years.
Both Tigers and Giants will now have to contest next weekend's preliminary semi-finals, with the former meeting Warrington Wolves.
Tony Smith's men were given a real scare by a spirited Widnes Vikings side making their first appearance in the play-offs, before eventually winning 22-19.
With Wolves trailing 18-0 after half an hour, a Joel Monaghan hat-trick helped turn the tide for the hosts who will now prepare for a meeting with Catalans Dragons.
Smith will be concerned, though, by a potentially serious injury to full back Matty Russell, who was carried from the field on a stretcher following a second-half collision.
Catalans enjoyed a last-gasp victory over Challenge Cup winners Leeds Rhinos, with the hosts having been on their way to a West Yorkshire derby with Huddersfield with just less than three minutes remaining.
Leading 20-18 at Headingley, Brian McDermott's men looked set to progress only for Sam Williams to go over and Thomas Bosc to add the extras - sending Catalans through 24-20.