Connor Jennings nodded home the decisive goal just two minutes before the end of the extra-time period, breaking Newport County hearts and sending Rovers fans — among them an elated Premier League referee Mike Dean — into delirium.
Newport was reduced to 10 men in the final minute of normal time when captain Mark O'Brien received a second yellow card. It was also been denied what it felt was a clear penalty in the second half when Jamille Matt was felled in the box, but he'd made a pass moments before the foul to a team-mate in an offside position, and the officials correctly denied the appeals.
Earlier in the match, both sides had gone close to opening the scoring, but neither could beat the goalkeepers, who both pulled of magnificent saves to keep the game scoreless until those dying minutes.
Tranmere will now look forward to next season as a League One outfit, while for Newport it's back to the grind of League Two football after what will feel like an absolutely heart-breaking loss.