Barnet manager Lawrie Sanchez claims his side's performance improved since their midweek game although Oxford beat them 2-0 at home.
Goals from Simon Heslop and Liam Davis sunk the Bees, and Sanchez took positives out of the encounter, but he insisted the team must get better for upcoming fixtures.
"I thought we played better than we did in midweek, but it's disappointing," he said.
"Perhaps we need more evening games. I've suggested to the chairman that we play more evening games.
"We'll have to play a lot better than we did today against Swindon. I think we've got a good enough squad to cause a lot of teams a lot of problems. We have a fully fit squad now so there's competition for places."