Jon Walters hit a hat-trick and David Wright, Tommy Miller (pen) and Pablo Couñago were also on the scoresheet as brilliant Town hammered ten-man Bristol City 6-0. The Blues, dominant from start to finish, were two goals in front at the break before Bradley Orr saw red for a professional foul.
As expected, Jim Magilton switched back to the 4-4-2 formation which has served him so well at home. Owen Garvan returned to the midfield alongside Tommy Miller, while Pablo Couñago rejoined Alan Lee up front and Billy Clarke regained his place on the left flank from Gary Roberts.
The game's first chance fell to City defender Louis Carey, but his header from Michael McIndoe's freekick on the left flew over Neil Alexander's crossbar.
On three, Jon Walters was sent away by an Alan Lee flick, but his shot scraped wide of the post.
The former Chester man wasn't to be denied his fifth goal of the season for too much longer. Two minutes later the striker-turned-right midfielder took the ball on a mazy dribble in from the right before firing a low shot from the edge of the area which beat Adriano Basso via a deflection.
David Noble's 25-yarder was hit straight at Neil Alexander, then Pablo Couñago shot narrowly wide from the 18-yard line. On 12 the Spaniard lobbed Basso from a Lee flick but also sent the ball over the crossbar.
Town's second goal came on the quarter-hour mark. The Blues broke quickly and Garvan played the ball wide to Walters on the right. The scorer of the opening goal crossed deep but the ball was cleared to the left, only for Lee to regain possession.
The Blues' top scorer sent the ball back into the box from where David Wright bulleted an unstoppable header beyond Basso for his second goal since moving to Portman Road in January.
It was all Town and a minute later Couñago found Lee on the edge of the area but the Irishman's shot was too close to Basso.
City lost central defender Louis Carey to injury in the 21st minute, the knock having been picked up earlier in the half when sending Couñago crashing to the floor with the ball well gone. Man mountain Jamie McCombe took over.
Marvin Elliott headed over Alexander's bar, then Basso claimed Lee's knockdown from Walters's cross from the right. On 36 Couñago shot straight at Basso after Garvan had nodded the ball into his path inside the area. Soon after, Danny Haynes replaced Alan Lee, the striker having picked up an ankle problem.
There was a rare scare for the Blues on 38 when Alexander came to the edge of his area to punch away a cross but failed to gain any distance. The ball dropped to McIndoe 20 yards out but, with the goal gaping, the ex-Wolves man weakly lobbed into the Town keeper's arms.
In injury time, Danny Haynes used to his pace to almost beat Basso to a ball played into the box, but the Robins keeper cleared.
Town had been much the better side against a Bristol City team which had hardly threatened. City had defended deeply when the Blues were in possession with Alan Lee and Pablo Couñago allowed to spend much of the half taking balls in to feet on the 18-yard line, while Town had broken quickly and effectively after Robins attacks had broken down.
The West Country side were out early ahead of the second half with former Luton striker Enoch Showunmi replacing David Noble as Gary Johnson's side switched to 4-4-2.
Three minutes after the break the Blues increased their lead. Haynes was sent away over the top with the Bristol City backline defending too far up the field. The England U19 striker took the ball into the area and, with Basso already appearing to be beaten, Bradley Orr tripped the Town striker as he prepared to slip the ball home.
Referee Nigel Miller had no alternative but to award a penalty and red card Orr for what was as obvious a goalscoring opportunity as you'll see. With Alan Lee off the field, Tommy Miller took over spotkick duties, hitting a low shot to Basso's left and into corner of the net for his second goal of the season.
Town were by now rampant against a side which looked well beaten. Haynes's strike was saved by Basso, prior to McIndoe sending a rare shot wide of Alexander's goal.
The fourth goal of the afternoon came in the 55th minute, Billy Clarke starting a Town break on the left, referee Miller allowing play to continue after the Irish U21 international had been fouled. Clarke found Garvan, who was about the play the ball into Jon Walters's path on the right when he was tackled, only for the ball to end up at the right midfielder's feet anyway. Walters took the ball on into the area before lashing a shot past Basso at his near post for his second of the game and his sixth of the season.
Ten minutes later, Pablo Couñago got his name on the scoresheet. The Spaniard received the ball on the right of the penalty area from Walters then tricked and turned his way past a couple of defenders, before slipping the ball past Basso with trademark subtlety.
It was now a case of how many the Blues would score with a goal looking likely almost every time City lost possession. Basso saved from Walters, then Billy Clarke shot over from 30 yards.
On 71 Couñago brilliantly sent Walters away through the middle from halfway, the Bristol City defence again caught by a Town break, the striker taking the ball into the area and beating Basso to complete his hat-trick with the Blues' sixth of the game and his seventh of the season.
Three minutes later, Town's hat-trick hero left the field to a standing ovation as Gary Roberts took over for the final 16 minutes. The former Accrington man slotted in on the left of midfield, Danny Haynes moved to right midfield and Billy Clarke joined Couñago up front. Alexander saved from Elliott, prior to Sylvain Legwinski replacing the outstanding Owen Garvan.
With 10 minutes remaining, Clarke and Couñago exchanged a one-two on the edge of the area, the Irishman hitting a shot which scraped under Basso and which looked set to go down as Town's seventh goal until it was hooked from under the bar by a defender.
In the closing stages, Darren Byfield shot over from the edge of the box, but a goal would have flattered the visitors, who had been completely outclassed throughout.
Another superb home display from the Blues, probably the best of the season, although against the poorest opposition we've seen at Portman Road in some time. Even before the sending off, Town were well on top and four or five goals looked on the cards at that stage.
City appeared to defend too deeply in the first half, allowing Town to play their football around the edge of the penalty area, then were constantly caught on the break when defending higher up the pitch against the pace of Danny Haynes in the second.
Keeper Basso and his backline had innumerable moments of hesitation and disorganisation and defeat of even greater proportions would have been little surprise. Town passed the ball around slickly and incisively throughout with some superb crossfield balls from Garvan and Couñago in particular.
Hat-trick hero Walters once again dominated proceedings on the right flank and finished brilliantly on all three occasions. Couñago's quick feet and clever passing were once again a huge factor in Town's victory, while Danny Haynes provided a massive threat after the break and deserved a goal, as did Billy Clarke.
Town's first 6-0 win since the defeat of Nottingham Forest by the same scoreline in March 2005. Walters's hat-trick was the first by a Town player since Alan Lee's in the 5-0 home defeat of Luton in October of last year, previously the highest win of Jim Magilton's managerial career.
The victory was the Blues' 11th at home on the trot and once again Town looked like a side well capable of being in the promotion shake-up come the end of the season, however, the enigma that is Town's failure to replicate that form away remains.
Town: Alexander, Wright, Harding, De Vos, Bruce, Garvan (Legwinski 79), Miller, Walters (Roberts 75), Clarke, Lee (Haynes 37), Couñago. Unused: Supple, Wilnis. Att: 22,020.