The Saints have named their former captain for the second successive week as he battles to overcome a persistent hamstring injury.
The fierce tackler, who replaces the injured Jarryd Allen, has been named in a forward pocket, and will be given until the last possible moment to prove his fitness.
He injured his hamstring in round 18 and has not played since.
The Saints have Michael Gardiner, Shane Birss and Aaron Fiora on stand-by should Ball fail to overcome his hamstring in time.
Hawthorn has made one change for the club's biggest match in seven years, recalling running defender Xavier Ellis for Saturday night's blockbuster.
Ellis has earned a recall after being an unlucky omission from the Hawks' first final.
Cameron Stokes is out of the side with hamstring tightness.
However there was relief for Alastair Clarkson after several other injury fears proved unfounded.
Chance Bateman has been named in the side despite rolling an ankle at training on Tuesday, while key defender Trent Croad – the man most likely to pick up Saints match-winner Nick Riewoldt – has also been named.
Stephen Gilham, Jarryd Morton and Travis Tuck are the Hawks' emergencies.
Premiership pair James Kelly and David Wojcinski have been recalled to the Geelong line-up for Friday night's preliminary final against the Western Bulldogs.
As expected, Brent Prismall (knee) and Paul Chapman (hamstring) are the two omissions from the Geelong team that belted St Kilda by 58 points in a qualifying final two weeks ago.
Both the Cats' inclusions haven't played AFL football for at least a month.
Kelly, who has battled a quad injury in recent weeks, returns to the team after playing his last match in round 20 against the Sydney Swans.
Wojcinski's lay-off has been even longer, with the dashing defender not having played senior football since round 15 against Fremantle – on July 12.
However the speedster did manage to overcome his Achilles injury late in the season, playing two VFL matches before continuing to train with the senior group.
David Johnson has been named an emergency along with forwards Ryan Gamble – who booted four goals against the Bulldogs in round 16 – and Shannon Byrnes.
Western Bulldogs coach Rodney Eade has stayed true to his word by naming an unchanged side to take on the premiers.
Eade hinted on Thursday morning that there were unlikely to be any changes to the side that convincingly beat the Sydney Swans in last week's second semi-final, and the coach delivered on his promise.
Adam Cooney, under a fitness cloud earlier this week due to illness and knee soreness, has been named as rover.
The emergencies are Andrejs Everitt, Farren Ray and youngster Callan Ward.
