The tighthead prop, who will join Gloucester this summer, came off the bench to play his part in a thrilling 23-22 success against Stade Français.
It was a monumental effort from the entire Saints 23 as they stormed back to slay the French giants.
Stade were in control at half-time, scoring three tries on their way to a 22-9 lead.
But Ben Foden’s try breathed new life into the Northampton bid and, despite a yellow card for Rory Hutchinson and a red for skipper Tom Wood, Saints still had enough in the tank to win it.
Denman helped to continue the forward momentum, ensuring his team continued to boss the scrum against a front row containing world class prop Rabah Slimani.
And it was a great way for Denman, who joined Saints from Rotherham Titans in the summer of 2013, to sign off as he helped his club secure Champions Cup rugby for next season.
“After a disappointing season, I was happy to play in the last game and get a win to keep the team in Europe for next year,” said Denman, who was making his 75th appearance in Saints colours.
“Hopefully they can push on and get back to the heights we were at before.”
The heights Denman refers to is the double-winning season of 2013/14.
The affable prop made 23 appearances during a campaign which encompassed glory in the Aviva Premiership and Amlin Challenge Cup.
Denman came off the bench in the European final, and he is grateful for the experience he has garnered at Franklin’s Gardens.
“I’ve had some great players around me,” he said.
“I learned a lot from Salesi when he was here. He was massive for me.
“Coming from Rotherham, he really helped to prep me for the game time and I learned a lot from him.
“Players like Dylan (Hartley) are awesome to just get the knowledge from and there are great players at this club.
“You’re learning every day.”
Denman’s good form for Saints even earned him an England Saxons call-up and he faced the Barbarians at Twickenham in 2015.
“It was a good day for me,” he said. “I enjoyed that.
“Hopefully I can go to Gloucester, kick on and get a bit more of that.”
Denman’s determination to succeed at Gloucester is enhanced by the fact he has struggled to get any game time at Saints in recent times.
He hasn’t started a match in either of the past two seasons, with Kieran Brookes and Paul Hill often the preferred options for the No.3 shirt.
And Denman said: “I’ve not been able to get the game time I want and sometimes you just have to move on to better yourself.
“That’s where we are now, but I’ve enjoyed it here, it’s a great set of lads who I’ve enjoyed playing alongside week in, week out and I can’t speak any higher of the lads.”
And Denman says his Saints team-mates are what he will miss most as he heads for a fresh start at Kingsholm this summer.
“Ever since I came from Rotherham, the lads have made me feel welcome,” Denman said.
“They’re my family now and it will be sad to leave them behind, but you have to move on.
“I’ve made friends for life and I’ve got massive respect for these lads.
“It’s been great.”
While Denman is clearly delighted that Saints will retain their place among Europe’s elite next season, he can’t hide his disappointment at how things have panned out since the club topped the Premiership regular season table for the first time, in 2015.
The 26-year-old said: “Obviously in the past two seasons we’ve not been where we hoped to be and that’s been a bit disappointing.
“But I’ve enjoyed my time here.
“It’s been really good.”