Coach Dean Pay was left scratching his head after a try by Dallin Watene-Zelezniak in the 15th minute was disallowed by the Bunker, in the Bulldogs' 15-8 loss to the Cowboys in Townsville on Thursday night.
Watene-Zelezniak was ruled to have lost possession in the act of grounding the ball early in the first half.
The Bulldogs remained in the contest until the final stages, until a Jordan Kahu field goal and Shane Wright try in the last five minutes sealed the win for the home side.
"It's ridiculous. When did he lose the ball? Where did he lose it? It goes up [to the Bunker with an on-field ruling of] a try," Pay said.
"We started really well and Dallin scores a try and they take it off us, I still can't work that out. I know it was a long way out but those things hurt you."
When asked if he thought Watene-Zelezniak dropped the ball, Pay said "No, I don't".
The loss ended the Bulldogs' slim finals chances on what was a night of celebration for the Cowboys as they played their last home game at 1300 Smiles Stadium.
"We came up and gave ourselves a really good shot at getting the two points," Pay said.
"We were expecting a really tight game, we knew it was going to be a struggle. I thought we fought to the death and fought really hard, and that's our team. We didn't get the result tonight but I'm really proud of them."
Pay said his team lost composure towards the end of the game and didn't create enough opportunities.
"We didn't take them and it came back to bite us in the end."
Next week the Bulldogs host Brisbane as they focus on finishing the season with a win and look ahead to next season.
"We'll get ourselves ready. We want to build on our performance against the Broncos. We’ll get ourselves ready for pre-season and get ourselves ready for next year," Pay said.