A disappointing game from Paulton leaves them questioning a poor season.
A lively start from both teams gave Josh Morgan Williams a chance to score with a volley that went just wide. He then had a volley tipped over the bar.
Both sides were cancelling each other with the referee booking players for seemingly petty offences.
Didcot took the lead just on the stroke of half time with Callum McNish taking the ball from Marlow Ayswayo slotting past debutant Adam Forster.
Rovers defended well in the second half and on the break Liam Monelle and Joe Hillard both had chances sailing narrowly over the bar.
The plus was that five of the Paulton side are teenagers with 18 year old Jordan Lovibond making his first Southern League start and performing well.
The Railwaymen took their other two goals within five minutes of each other in the last eight minutes with Felipe Barcelos racing away down the left and shooting home then in the final minutes sub Sam Barder broke down the wing as Forster tried to deflect the ball only for it to crawl into the net.
The score flatered Diddy who secured their place in the play offs with a trip on Wednesday to face Wimborne Town.
Paulton finish off the season with the Somerset cup final against Weston Super Mare on Tuesday 8 May.