The Cronulla Sharks must defeat against the Canberra Raiders to avoid becoming the NRL's least successful finals team.

No team in the NRL era has ever qualified for the finals without beating a fellow top eight team throughout the season.

The Sharks will have to battle the Raiders without their best player in Shaun Johnson, who suffered an achilles injury last weekend.

The Sharks' record against the top-eight teams leaves a lot to be desired, as they have an aggregate losing margin of 212-106 against the fellow finals-bound sides.

They concede 30.2 points per game against their top 8 rivals.

Cronulla have beaten the Titans, Cowboys and Warriors twice this season in their pursuit for a finals berth.

A win against Canberra in round 20 will avoid the label as one of the NRL's most disappointing finals sides in the game's history.