The hosts opened the scoring after nine minutes when Jeffrey Schlupp turned home a Michael Olise cross, but were undone when Burnley levelled just moments into the second-half and then held their own.
Reflecting on the game, Vieira said: “It was difficult. We knew how challenging that game was going to be, and we conceded the goal where we had a bit too much space in our back four and knew we needed to be compact. [In] that moment of a lack of concentration we conceded.
“We knew how good they were in playing the long ball. We managed it quite well but in the end we conceded that goal and that took the win away from us.”