North End were beaten by two Gary Madine goals at Hillsborough on Saturday lunchtime and furious manager Graham Westley immediately accused four players of informing the Wednesday camp of their intended team and shape in his post-match press conference.
However, Ridsdale, who appointed Westley in January, insists the actions were not malicious.
"What Graham said after the game on Saturday was true," Ridsdale told the Lancashire Evening Post. "It was almost said in the heat of the moment after the disappointment of a defeat, and it was disappointing that our pre-match preparations were known to the opposition in advance.
"I'm aware categorically where the information came from, although I don't think it was done maliciously.
"It's unfortunate that it happened, but it's time to draw a line under it and move on in order to focus on our game against MK Dons on Saturday."
The Professional Footballers' Association does not believe any of Preston's players deliberately intended to undermine their team.
The PFA's assistant chief executive John Bramhall told Press Association Sport: "We've spoken with one of the players already and a couple have commented on Twitter that they could not believe any of their team-mates would deliberately jeopardise their team's chances."
He added: "The chairman has since said information was given, but that there was no intention to undermine their team-mates and that it was not malicious.
"He accepts that and we would support that - that the information has been inadvertently leaked."
Bramhall said the players' union would continue to monitor the situation, but that Ridsdale's comments had helped to diffuse the situation.
Bramhall added: "You would hope managers would be more mindful of their comments. An allegation had been made. It's a serious allegation against his players' integrity, but you have to accept the chairman's comments that they had been made in the heat of the moment.
"It's difficult to understand why players would jeopardise the chances of their team getting a result and risk putting their team-mates closer to relegation."
Preston duo Neil Mellor and Iain Hume have taken to Twitter to defend themselves and their team-mates.
Mellor, who was not involved at Hillsborough, tweeted: "Wasn't involved with game sat v owls but can't believe this story my team mates would leak the team."
Fellow striker Iain Hume, who was an unused substitute, said: "I can categorically say I never have and never would tell anyone any inside info! 2 be honest I think it's all utter rubbish!
"...the comments in my eyes came from somebody tryin 2 unsettle our dressin room! My opinion 2 be honest! Can't see and....
"hopefully proven right that any of my team mates would divulge info like that! We're close and it needs 2 stay that way!"