The Power went down by nine points in humid conditions at TIO Stadium in Darwin, relinquishing a half-time lead after a lacklustre third quarter saw the Bulldogs score five goals to none.
Hinkley's men made a late fourth-quarter charge, but fell short to record their fifth straight loss, which came after a stirring 5-0 start the year.
The Power coach felt the loss was his team’s worst "by a long way" this season, and questioned the hunger of his players.
"It's been a really poor night for us," Hinkley said.
"I think it just came down to a little bit more want in the third quarter. They wanted the win. They wanted to win the ball, they won the contested possession really well.
"They just wanted to win the game more than we did, which was disappointing.
"It should be very damning because we should never have let that game go the way it went."
The Power play the winless Greater Western Sydney after next week’s bye, but then face a torrid month with matches against the Sydney Swans, Collingwood, Essendon and Hawthorn to follow.
Adding to Hinkley's woes, ruckman Jarrad Redden looks to have suffered a season-ending right shoulder injury. The 22-year-old left the field in agony in the final term after being injured in a ruck contest.
"It popped out a little bit, sublaxed a little," Hinkley said.
"He's going to be an issue for us. We've got to make a decision on how bad that will be, and whether it will require surgery now to end his season, or whether we can push on a little bit more.
"We won't know until we get the scans, but my first thought would say we wouldn't be taking too many risks and we would be getting him repaired quite quickly."
Jacqui Reed is a reporter at AFL Media. Follow her on Twitter @JacquiReedAFL
