Both teams looked poised for a share of the spoils at Vale Park, only for the 27-year-old to steal the points in the dying minutes with a right-footed strike.
Speaking to BBC Sport, the 43-year-old coach rued the general performance of his side, but he believes that grinding out victories is the hallmark of a special team.
"It was a bit of magic from the big man, a great finish," he said. "We needed his bit of individual brilliance to win us the game, but to be honest we never really got going.
"But it's always the sign of a great team when you don't play well but still win the game, so I think it is key for us."
Posh, who kept to within a point of leaders Leyton Orient in League One, will resume their quest to reach the summit by hosting Shrewsbury Town at London Road next Saturday.