Adam Armstrong scored his second successive Ewood Park hat-trick as Blackburn hammered Birmingham 5-2.
After a Thomas Kaminski error allowed Kristian Pedersen to put Birmingham ahead, Armstrong sprung into action to lead Rovers to an impressive victory in their final game of the season.
He confidently hammered in a 27th-minute penalty to restore parity before Ben Brereton's composed finish in first-half injury time deservedly put the hosts ahead.
And although Lukas Jutkiewicz headed an equaliser just after the restart, Rovers took the game away from Blues with a devastating display of finishing to give a scoreline that reflected their dominance.
Armstrong's 71st-minute shot squirmed under Connal Trueman to restore Blackburn's advantage and they wrapped things up with two goals in three minutes late on - an outrageous Harvey Elliott finish before Armstrong completed his hat-trick to make it 29 for the season.
Armstrong's final goal ensured Blackburn signed off a disappointing campaign with a second successive 5-2 win at Ewood, having also dispatched Huddersfield by the same scoreline.
It was Birmingham's second successive defeat but they can look back on the last 10 games with relief, having pulled safe from any danger.
Blackburn had a more youthful look with Jacob Davenport and John Buckley both starting, while Blues stand-in manager Craig Gardner selected his brother Gary to skipper the side.
Armstrong struck the crossbar with an early free-kick before Birmingham were handed the lead in the 22nd minute when a harmless free-kick was dropped by Kaminski at the feet of Pedersen who could not miss.
The lead lasted five minutes as Jonathan Leko needlessly shoved Amari'i Bell over in the box and from the resulting spot kick, Armstrong lashed home his fifth goal in three games.
Trueman produced a fine save to deny Gallagher but could do nothing in injury time when Brereton outmuscled Pedersen before confidently slotting past the goalkeeper for his seventh this season.
Gardner introduced Jutkiewicz at half-time and he took just five minutes to make an impact as he got onto the end of Steve Seddon's pinpoint cross to easily head beyond Kaminski from six yards.
Blues 'keeper Trueman once again made a brilliant save, this time from Armstrong, who hammered in a low shot only to see it parried away.
The 24-year-old was not to be denied 19 minutes from time though, when he shifted the ball onto his left foot and fired underneath Trueman, who will be disappointed to be beaten.
Late devastating finish confirmed Blackburn's superiority, as two goals in quick succession did the damage.
First, Elliott ran on to a Corry Evans pass before exquisitely lifting the ball over Trueman in the 83rd minute.
Then Armstrong completed his hat-trick, wriggling free in the box and slamming the ball past Trueman for his seventh in three games as Rovers comfortably romped home.
What the managers said...
Blackburn's Tony Mowbray: "He [Armstrong] could have had 40 rather than 29 but that's okay, that's good that he's thinking like that, that he's disappointed he hasn't scored more. For Adam's sake let's hope the phone rings and someone offers us a ridiculous amount of money, we shake him by the hand and we say 'go and bang in loads of goals in the Premier League' and we'll use some of that money in the team and can find another striker who can bang loads of goals in.
"That's football, that's happened since the game started. He's shown what a talent he is, he could have had five today. My analyst is saying the first one wasn't offside but there you go. Let's keep rolling, see what the summer brings for Adam and the team."
Birmingham coach Craig Gardner: "We were constantly in touch with the gaffer before, during half-time, and after, and once we got safe, we had a plan and that was to give the players what they deserve. The younger players have had a great season with the under-23s and under-18s and we only think it's only fair to give them the opportunity they deserve, and that creates that pathway from the Academy to the first team which I know Lee wants to do.
"That big step up for them is important, and to play back-to-back game in the Championship is a real test, but I think the young players and the players that haven't had that much game time coped with it quite well because they had a strong team out today and we matched them for pretty much most of the game. Probably the last half hour we faded, which is expected, but it's okay."