"We had a couple of opportunities early on where we might have been able to get into a bigger lead but it didn't work out - that's rugby league," said Maguire.
"Full credit to Saints because they built a bit more pressure than we did."
And for Saints boss Royce Simmons - a former Penrith Panthers coach - the victory had its origins in his side's defence.
"We had parts of the game where we didn't get much ball but our defence held on," said Simmons.
Meanwhile, former Kangaroos hooker Danny Buderus helped Leeds to seal a shock grand final berth - then revealed he's quitting the Rhinos to join Newcastle Knights.
Buderus helped the Rhinos create history with a 26-24 win over Warrington - skipper Kevin Sinfield's last-gasp goal making them the first side to reach the final having finished outside the top three in the regular season.
Buderus had revealed in July that former employers the Knights had been interested in bringing him home, despite having a year left to run on his Leeds deal.
And the 33-year-old chose the post-match celebrations after downing the Wolves as the time to reveal their overtures had been successful.
"To go home with an appearance at Old Trafford is a dream script," said Buderus, who will link up with new Knights coach Wayne Bennett on October 8 after the NRL grand final on Sunday.
"The Rhinos have wished me well which is great. But we now want to go to Old Trafford and win it.
"We've got some momentum and that makes us a dangerous team."
- AAP
