The France right-back faced the media at Wembley after Chelsea's 1-0 defeat, a result settled by Antoine Semenyo's backheel flick in the 72nd minute. Gusto felt the performance deserved more, pointing to Chelsea's energy and organisation throughout a match they dominated in spells.
"I think we matched them in every point in the game. We showed a lot of energy and I think the plan was good. It was just a matter of not having that bit of luck. We didn't have the final touches today."
He was candid about the emotional toll of the defeat, but focused quickly on what comes next.
"We're disappointed. We wanted to win this game, but it didn't happen. So it's a tough feeling for us, for the fans, and for the club. To lose 1-0 this way is tough to accept, but we have to move forward now and stay together."
Chelsea had three penalty appeals turned down across the 90 minutes and Erling Haaland had a first-half goal ruled out for offside at the other end. Despite the fine margins, Gusto declined to point to those decisions as decisive.
Chelsea return to Premier League action on Tuesday at Stamford Bridge, hosting Tottenham Hotspur in their final home game of the season. The club sit outside the top four and require results to go their way to secure European football for next season.
"The season is not finished — there are two games left. We are disappointed tonight, but we have to move forward now. We have two games left in the Premier League and we have to fight again."
Incoming manager Xabi Alonso, confirmed on Sunday, is expected to be present at Stamford Bridge on Tuesday.