The striker made the most of a place in the starting line-up, scoring in a 4-2 win away to Cheltenham Town in the Johnstone’s Paint Trophy.
It ended a run without a goal which stretched back 21 games and almost eight months – more than double his previous longest drought at United.
The 28-year-old, known as Beano, insisted confidence had never been an issue during the long wait for a goal and he is keen to regain a central role now the run is over.
He said: “In training, I’m scoring goals day-in day-out, it’s not like I’m lacking in confidence.
“I know I can score goals – 80 for the club in four years shows I can do that.
“I read somewhere my last goal was back in February. Obviously it’s been unfortunate this season I haven’t played as many games as I would have liked, but I’m desperate to get out there and score some goals.
“We’re a close group of players and we want to play every week.
“But whatever team is picked, I can assure the fans that the XI out there are going to do the best they can to get the win.”
This summer the U’s turned down three bids from Bristol Rovers, rising to £200,000, with manager Chris Wilder saying his longest-serving player was his No 1 striker.
The U’s boss has handed more starts to Deane Smalley (eight) and Tom Craddock (seven) than Constable (six) so far this season, but was delighted with the breakthrough at Cheltenham.
“That boy is a goalscorer,” he said.
“Yes, there are other bits and pieces of the game that we and him have to work on, but you could see he stuck his chest out as soon as he scored – he was off and running.
“Hopefully he can kick on now. He led the line with Tommy really well and caused Cheltenham problems all night.”
Constable has made a habit in his career of following troughs with a glut of goals.
The striker said: “They do seem to come in patches, so hopefully I can go into the next game against Port Vale full of confidence and maybe get another.”