Irishman Clancy, who left Easter Road in January following an injury-hit 18 months, has signed until the end of the season after defenders Frazer Wright and Tam Scobbie both succumbed to ankle ligament injuries during last weekend's defeat by Inverness.
Wright is out for at least a month while Scobbie will have an operation next week and has joined knee-injury victim Murray Davidson on the sidelines for the rest of the campaign.
The versatile defender could now be involved in the Scottish Premiership fixture at Aberdeen on Saturday as Saints bid to build on their 3-0 midweek win over Motherwell.
- Sports & Recreation
- Tam Scobbie
- Frazer Wright
- Murray Davidson