Season over with still two games to play, Tony Mowbray admitted Rovers lacked the quality to trouble Millwall’s defence as they lost for a fourth time since the re-start to end any lingering play-off hopes.

Mason Bennett’s strike 20 minutes in was all it needed for the Lions who are right in the top six mix as they ended a poor run of form at the New Den.

Rovers had double the possession of the hosts, but struggled to test Bartosz Bialkowski apart from strikes in either half from Adam Armstrong, while Joe Rankin-Costello went close to an equaliser with the final kick.

Mowbray’s side knew nothing less than three wins from their remaining fixtures would be enough to keep their faint top six hopes alive, but they fell short in south London, particularly in a first half that lacked any energy, looking little like a team who had no margin for error.

Mowbray said: “That’s the disappointment, we can’t do anything about it now, we all knew what was at stake, as Millwall did, it wasn’t as though we were playing a dead rubber against a team who it didn’t matter for.

“They had a lot at stake as well and ultimately they did what they did, played how they play and got a 1-0 victory. It was hard for us to get over them or round them, or through them, and ultimately didn’t score a goal.”

Millwall felt comfortable to sit on their one goal lead given to them by Bennett as he turned home from close range after a mishit Tom Bradshaw shot found its way to him.

Jed Wallace and Bradshaw did force saves out of Christian Walton, but it was slim pickings at the other end in terms of clear-cut chances, despite Rovers’ dominance of possession.

“The result isn’t what we wanted, performance you’d have to say wasn’t what we wanted. We huffed and puffed and couldn’t break down that defence,” the manager added.

“We knew what to expect, they’re big, strong, expressive, they play a lot of balls forward and tried to go over the top.

“We had a lot of the ball but didn’t have enough quality and couldn’t ultimately break them down. We didn’t have that little bit of craft or individuality to make the difference, someone who could have put it between someone’s legs and bent it in to the far corner, a goal out of nothing.

“A lot of the play around their box came to nothing, fizzled out, and I think the worst thing was that they scored because they could then sit on that, waste time, I think the officials, once again, I don’t want to spend every after match moaning about the officials, but there was a lot of stuff that they needed to be quicker on to move the game on.

“Everything seemed to be stopped and slowed down. It was that time of game, a frustrating game, and we lacked the quality down to break a big, strong organised defence down, and we’re left frustrated.”

After an insipid first half, Mowbray turned to his bench at the break, sending on Sam Gallagher and Joe Rothwell, as well as switching formation, playing without a recognised centre forward.

“The first half just wasn’t good enough in my opinion. We lacked ideas, we lacked energy, a lack of individuality, it needed changing,” he said.

“The frustration was that the team felt ready before the game, adrenaline levels were high, knew what was at stake, but there are two teams playing and Millwall weren’t sat in their dressing room not bothered about the game.

“We knew we had to go and compete, and while we did compete, we lacked the quality in the first half, we didn’t pick the right passes, making the right runs, Millwall got on the front foot and made life difficult for us.

“We kept just booting the ball on to their big centre halves’ heads, second half we had control of the game, pushed them back, but didn’t work their keeper enough around the edge of the box, didn’t put the right quality in.

“It turned in to a really frustrating night, bitty stop-start, and not a very nice game.”