Before the game Middlesbrough manager Steve McClaren called on his players to go all-out to achieve their best-ever points total in the Premier League.
His players responded in style with an exciting game of goals, action and drama.
No doubt McClaren and Birmingham boss Steve Bruce will be unhappy over the performances of their defences but the fans lapped up this feast of attacking football.
Middlesbrough could finish in the top half of the league on this form, but for Birmingham it was a shattering blow to their hopes of fourth spot and a Champions League place.
Boro scored five goals for the first time this season yet, amazingly, their best player was goalkeeper Mark Schwarzer.
The Australian international performed heroics as Birmingham fought back to try and rescue something from the game.
Schwarzer defied City on several occasions and shared top individual honours with City striker Mikael Forssell.
The Finnish international was easily the outstanding forward on the pitch and certainly did not deserve to figure on the losing side.
It was sweet revenge for Middlesbrough following their 3-1 defeat St. Andrew's three days after their Carling Cup final success over Bolton Wanderers at the Millennium Stadium.
It proved not to be a happy weekend for Birmingham who endured an eight-hour road journey to the North East owing to a horrific car crash on the A1.
McClaren has often been criticised by fans this season for operating with only one striker at the Riverside Stadium.
On this occasion McClaren made a bolder approach and the two-striker formation paid off.
Inside 21 minutes Boro were two goals up and playing delightful football.
Gaizka Mendieta opened the scoring after five minutes. From a Juninho pass, Mendieta provided a clinical finish with a low drive into the corner of the net.
Massimo Maccarone increased the lead after 21 minutes.
The club's record buy has been the butt of fans' taunts this season but there were cheers for the Italian as he scored from close range following a Mendieta pass.
City hit back and took advantage of a lapse by Danny Mills. The England international was dispossessed by Stan Lazaridis out on the left wing.
Lazaridis darted forward to provide a pass for Forssell to score his 15th goal of the season.
The visiting defence was still all at sea, with six players inside the six-yard box, when Southgate increased Middlesbrough's lead on 30 minutes. Southgate took advantage of slack marking following a Mendieta corner and a Mills header.
Before and after the goal, however, Schwarzer denied Birmingham with a series of brilliant saves.
No wonder the Australian looked dejected when Clinton Morrison pulled a goal back for Birmingham just before the break.
Nobody could argue that Birmingham did not deserve this goal, but Boro restored their two-goal advantage in stoppage time.
Maccarone took the ball round Martin Taylor and left Maik Taylor helpless with a brilliant shot into the roof of the net.
So Middlesbrough went into the break with a 4-2 lead. Yet no one in the 30,000 crowd would have been surprised had Birmingham been level or even ahead.
There was an anti-climax feeling at the start of the second half. The pace was slower after a pulsating 45-minute period.
The Birmingham players must have received a half-time roasting from an angry Bruce. They came out fighting and dominated the early stages of the second half.
Forssell, who was easily the best outfield player on view, pulled a goal back after 59 minutes.
McClaren then introduced three substitutes to try and keep the points in the bag.
The tension built up for an exciting finale with Szilard Nemeth sending the home fans home happy with a stoppage-time goal.
Both managers praised Schwarzer for his performance.
McClaren said: "I don't think you will see a better goalkeeping display this season.
"It was a bizarre game in a way. We scored five goals yet Schwarzer was our outstanding player." Bruce joined in the tributes: "Schwarzer gave an unbelievable display. How we were 4-2 down at the interval is mind blowing. I don't think I have seen such outstanding saves in one game. Schwarzer made two quality saves." McClaren said he was delighted over the win for the fans, adding: "There were some great goals, lots of mistakes, and we got three welcome points.
"I am delighted that Massimo Maccarone scored two goals. He has had a difficult time settling in but his ability is unquestionable. His second goal was magnificent." Bruce was bitterly disappointed over defensive errors and the failure to collect at least one point.
"You cannot legislate for individual errors. I thought that we were fantastic today and that we bossed the game.
"To be beaten by five is a kick in the teeth.
"You get games like that in a season. All you can do is scratch your head and wonder." Man of the Match Mark Schwarzer - a world class display, that outshone some outstanding attacking play from both sides.