Portsmouth advanced to the the Quarter Finals as goals from John Marquis and Ellis Harrison were enough to cancel out Caolan Lavery's ninth goal of the season as Kenny Jackett's Pompey remained in the competition they won last season.
The Saddlers were not without their chances and could've scored via birthday-boy Elijah Adebayo, the 22-year-old seeing a penalty saved by former Walsall 'keeper Craig MacGillivray.
Dutton, who was answering questions in place of manager Darrell Clarke, insisted he was proud of the team's overall display, admitting the performance was a major improvement upon some of the games at the start of the campaign.
Speaking to the assembled media, Brian said; "Yeah, we’re proud. That performance was chalk and cheese from the games at the beginning of the season, in terms of digging in and trying to get the win and giving the fans something to cheer about.
"I thought we pushed Portsmouth all the way there, even after going 2-0 down the lads didn’t lose belief. It just shows what a positive moment we’re in, in the season at the moment, to carry on going against a top team like Portsmouth.
"Full credit. The gaffer has touched on it, the game in essence is in between both boxes. Defending your own and then taking your chances on the other end. I wouldn’t say we definitely should have won the game, but I’m sure if we broke down the opportunities it would be very close. If not, we would have just pipped them for quality of chances."