Penrith's now guaranteed a top two finish and a home qualifying final.
The Panthers will secure the minor premiership as early as tomorrow (Sunday) if the Melbourne Storm don't beat the North Queensland Cowboys.
Meanwhile, the Bulldogs are poised to finish with the competition's wooden spoon after falling to their 16th defeat from 18 matches.
They've been beaten 32-20 by the Manly Sea Eagles in Sydney.
Manly's now 10th, level on points with the Warriors who play the Cronulla Sharks tomorrow night.