St Kilda captain Nick Riewoldt says his team lacked hunger in their loss to North Melbourne on Sunday.
The Saints slumped to ninth on the ladder with a 6-7 record following the 33-point loss to the Kangaroos, who climbed to eighth with a 7-6 record.
St Kilda led by 26 points early in the second quarter at Etihad Stadium before conceding 14 of the last 20 goals.
"It's hard at this stage to put a finger on exactly what went wrong," Riewoldt told reporters at St Kilda's recovery session on Monday.
"When you put on a performance like that it's going to be more than one thing.
"Our ability to defend all across the ground was pretty poor and they were able to put a big score on the board.
"They beat us in contested ball, they smashed us in the clearances and they were probably a bit hungrier.
"It probably looked that way to the majority of people watching.
"We made some pretty ordinary errors. Every time we turned it over, they seemed to get it down the other end and score pretty easily, which is disappointing."
The Saints face the in-form Essendon on Saturday at Etihad Stadium, where a loss could see them slip as low as 13th depending on other results.
"We've put ourselves in a position now where every week is a really important game. This week's no different," Riewoldt said.
"It's good that we get to come out and test ourselves against one of the best teams in the competition.
"It's a good chance to rebound."
Forward Rhys Stanley (hamstring) and defender Jason Blake (ankle) were absent from the recovery session at St Kilda sea baths, opting for treatment at the Saints' headquarters in Seaford.
With Brendan Goddard facing a two-match suspension after being cited for striking by the match review panel on Monday, the club is sweating on scans for Stanley and Blake.
"I've got my fingers crossed that they're okay," Riewoldt said.
"Rhys has missed a lot of footy with his hamstring. He's a promising, emerging player who gives us a bit of flexibility up forward and certainly through the ruck as well."And we all know what a great player Blakey has been."