Hibernian head coach Paul Heckingbottom insists anxiety from the club's supporters was a factor as St Johnstone claimed a point with the last touch of the game.
Saints defender Jason Kerr headed in a deserved 94th-minute equaliser following a period of sustained pressure from the visitors to earn a 2-2 draw.
Hibs fans had made their feelings clear as early as the 60th minute when they booed the decision to replace playmaker Scott Allan.
Michael O'Halloran cancelled out Adam Jackson's first-half opener in the 68th minute but Flo Kamberi restored Hibs' lead 60 seconds later.
St Johnstone had Hibs on the ropes before Kerr struck and Heckingbottom insists the apprehension in the stands did not help.
Heckingbottom, who claimed the visitors' second goal was offside, said: "We were trying to get the boys to relax but the whole stadium was anxious and that spread to the players.
"We are drawing at home and we will draw many more at home this season, without a doubt. It doesn't help the players – 100 per cent.
"I think they need to encourage more. I don't want them to draw back because you want to feel the stadium alive.
"But you could see that we were trying to calm them and tell them to stay calm and relaxed, but anxiety was an issue.
"If the fans can stay calm and if something good does happen, then get behind them."
Asked about the booing when Allan was replaced by Daryl Horgan, Heckingbottom said: "I didn't know there was a law against taking him off.
"No player's going to play 90 minutes every game. I've worked with Scott all week and know what he's been like.
"He's not been at his best in training. He's played 120 minutes last week (against Morton) and was carrying a knock.
"I didn't bring him off because he was injured but he was suffering. That'll happen."
St Johnstone left Easter Road with renewed confidence following a difficult start to the season.
Manager Tommy Wright, whose side failed to get out of their Betfred Cup group and remain with just one victory from seven outings, said: "We are disappointed to lose a goal from a set-play but I think apart from the goal we totally dominated the game.
"Hibs are always a threat and we went to sleep for their second goal, which let them back in the game.
"We showed character, we kept going and got our reward at the end. Hibs fans were quiet today and that was because of our performance."