St Johnstone boss Tommy Wright has pointed to his own team as an example of why banking on Hearts' poor recent form can be fraught with danger.
Since losing 6-0 at home to Celtic on October 7 in their fourth successive defeat, the Perth side have won five and drawn one of their last six Ladbrokes Premiership fixtures.
Craig Levein's team, by sharp contrast, have lost five and drawn one of their last six games and are now just two points ahead of fifth-placed Saints having played a game more.
However, ahead of their meeting at MacDiarmid Park on Wednesday night, the Northern Irishman said: "Form can change so quickly.
"People would have said playing us after Celtic beat us was the perfect time and look what happened.
"Managers don't sit and think 'they've lost three'...you think the other way, that they haven't won so they are due to pick up points.
"So it doesn't enter into my psyche or the players' psyche.
"Their form is not good but they are still ahead of us. It just shows you how tough this league is.
"They were unbeaten are the top of the league then all of a sudden the goals dry up and they slip down the league a bit.
"They will be disappointed with the run they are on but Craig is experienced enough to know how quickly it turns round."
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