Robert Jennings marked his return from injury with a try as South Sydney Rabbitohs sealed a top-four NRL finish with a 51-10 thumping of Wests Tigers in their last match of the regular season.

Prolific centre Jennings took his tally to 18 tries in as many games in a one-sided contest at ANZ Stadium, where the Bunnies ended a three-match losing streak to gain momentum for the finals.

A hamstring injury sustained by Sam Burgess will be a concern for Rabbitohs head coach Anthony Seibold, but that should not overshadow a ruthless eight-try drubbing, Adam Reynolds scoring 21 points for his title-chasing side.

Chris Lawrence got on the end of a brilliant kick from Benji Marshall - who signed a new deal along with Robbie Farah on Wednesday - to put the Tigers in front just three minutes in as they strived to end the season on a high note after failing to secure a top-eight finish.

The Rabbitohs hit back when Reynolds - fit again following a hamstring problem - finished in the corner but another clever kick from Marshall put David Nofoaluma in for a second Tigers try.

It was one-way traffic from then on, Angus Crichton crossing and Cody Walker weaving his way through to go over just before half-time, Reynolds converting to put the home side 22-10 up.

Campbell Graham finished a slick move and Reynolds touched down as the Bunnies put on a show, with Alex Johnston, Tom Burgess and John Sutton adding further tries.

Prop Jason Clark was only just on target with a conversion as the home side rubbed salt into the wounds ahead of a potential finals clash with rivals Sydney Roosters and Reynolds slotted over a drop goal to complete the rout.