Tranmere took the lead shortly after half time on 48 minutes with a close range goal from Anthony Kay.
On 57 minutes Simon Cox was through on goal when he was fouled on the edge of the box. Goodinson was shown a straight red card, and Swindon were awarded a free kick which Timlin look, but he was headed away by the wall.
Paynter struck the post, but that was the closest Swindon came all game.
Overall an average game, where both keepers had an quiet game. An 0-0 draw would have been a fair result. Swindon's next game in Tuesday evening in the local home derby game against bottom of the table Cheltenham Town.