St Helens joint-captain Paul Wellens says Friday's 19-6 victory over Huddersfield can spur his team on to the Super League Grand Final.
The full-back scored a try on his 400th appearance for the club.
Wellens, 31, told BBC Radio Merseyside: "That's the first time we've beaten a side in the top four so that's a monkey off our backs.
"It's certainly something we can build on and look to improve on and make a real assault on Old Trafford."
Meanwhile, St Helens have confirmed forward Tony Puletua is set to return to the squad ahead of the play-offs after scans revealed he does not need an operation on a damaged shoulder.
It was feared the 32-year-old could miss the run-in due to an injured rotator cuff, but instead he will now undergo rehab.
"It's great news," said Saints coach Royce Simmons. "TP is an integral part of the team and we're delighted he doesn't need surgery."