Portsmouth legend Guy Whittingham scored on his return to his old club - but it was only enough to claim a share of the points for Alan Ball's side.
Whittingham, who joined Portsmouth from the army 11 years ago, returned to Fratton Park in the second game of his loan spell from Sheffield Wednesday and got his name on the score sheet in the 17th minute.
The former soldier, who scored 88 goals in 160 league games for Portsmouth until he left them to join Aston Villa in 1993, showed he has lost none of his predatory instinct when he nicked the ball away from Jeff Peron to open the scoring for the home side.
Peron deserved much of the credit as he skipped past three Tranmere defenders before rounding goalkeeper Danny Coyne - only to find Whittingham waiting in the six yard box to pinch the ball off his toe and smash it into an empty net.
Portsmouth's lead was always going to be short lived as Tranmere piled forward, and it needed a desperate goal-line clearance from captain Adrian Whitbread to deny Scott Taylor claiming an equaliser just before the break.
A mistake by Greek International Michaelis Vlachos allowed Taylor in and he had beaten goalkeeper Andy Petterson. But Whitbread slid in to prevent Taylor's effort crossing the line at the last minute.
Moments later a mistake by the ineffective Fitzroy Simpson handed Tranmere the chance they had been waiting for.
Skipper Kenny Irons robbed Simpson of possession and floated in a perfect centre which caused chaos in the Portsmouth six yard box.
Frenchman George Santos forced Petterson to drop the ball and Taylor arrived to nudge it over the line in a melee inside the six yard box.
In the second half Portsmouth hung on but there were injury worries for Tranmere who had already lost Lee Jones to a knee problem in the first half.
Skipper Irons was carried off on a stretcher following a tussle with Peron after 88 minutes and his injury looked serious.