Posh are not yet mathematically down but Gannon, their third manager of the season, is resigned to a League One campaign next season.
"We have to put ourselves out of our misery and accept that we are going down,” he said.
"We would need to get three times as many wins as the club has managed all to season to even stand a chance of staying up. We don't have the depth of quality and we have to be realistic in that we are down.
"We haven't shown the technical quality required to hit the target and challenge to win games and that was the case again."
Coventry’s victory at London Road came thanks to a goal from striker Jonathan Stead.
Posh were promoted to the Championship in the summer after finishing second in League One under Darren Ferguson.
Ferguson was sacked in November after his side struggled to adapt to life in the second tier.
His replacement Mark Cooper, who left Kettering to take control, fared little better and was relieved of his duties after winning just one of his 12 games in charge. Gannon took charge at the beginning of February. | 
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