Hill had been sidelined since last year's Lions tour of New Zealand, having sustained the injury during the first Test defeat in Christchurch.
A long period of rehabilitation followed, but early signs were encouraging against the Saints as Hill touched down from the back of a maul to claim Saracens' opening try.
French star Thomas Castaignede, who has been out with calf muscle trouble, also played - as did Saracens' rugby league recruit Andy Farrell.
"It was a really good performance, especially from some of the older guys who were coming back from injury," said Saracens A coach Mike Hynard.
"The plan for 'Hilly' was to only play for the first half, and it is great to see him come through unscathed - and likewise for Thomas.
"It's good to see guys like that come into the team wanting to do well and not just going through the motions. It is also really good experience for the young guys who are in the side."