The Tigers remain fourth in the table despite slipping to a 2-1 defeat at Cardiff at the weekend in their third match in eight days.
Hull striker Jay Simpson had an effort ruled out for hand-ball just before half-time, while Robert Koren's last-minute strike came too late to affect the result.
Bruce blamed tiredness after admitting his players were second best in the Welsh capital.
"It was our third game in a week and I toyed with changing things around, but hindsight is a wonderful thing," said Bruce after his side's sixth defeat of the season.
"When I look at us, our worst performances are in the third game (of the week). We'll learn from it and I'll learn for next time."