Robbie Farah inspired Wests Tigers to a 20-16 win over the Dragons at Jubilee Oval, as the home side slipped out of the NRL top two.
It was just St George Illawarra's fifth loss of the season, their late rally - tries to Gareth Widdop and Matt Dufty - coming up just short.
The Dragons had led the ladder for 14 of the first 16 rounds, but their first home reverse of the year dropped them two points behind the Rabbitohs.
They suffered a State of Origin hangover, with all five Origin players backing up.
Farah, making just the second appearance of his second spell with the Tigers following his mid-season switch from South Sydney, was crucial in their three tries.
The veteran hooker's kicking and long cut-out passes were particularly effective in his 249th NRL game.
Luke Brooks, playing his 100th game, crossed for the visitors' opening try after Kevin Naiqama had had a four-pointer over-ruled. Ben Hunt hit back four minutes later, with the teams going in level at 6-6.
Again the Tigers were first to score after the break, through Corey Thompson, and this time they padded their lead thanks to David Nofoaluma's effort.
Esan Marsters, who converted all three tries, tacked on a penalty goal 13 minutes from time.
Down 20-6, the Dragons couldn't quite complete a late revival as the Tigers won at the venue for the first time since 2005.
Benji Marshall helped keep them out in the final minute when he put a 40-metre grubber kick into touch to wind down the clock.
Wests Tigers are 3.50 to win their next game against South Sydney, who are 1.33.
The Tigers are 1.90 with a 9.5-points start.
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