Goals from Will Nightingale and Jack Rudoni on 21 and 25 minutes have given AFC Wimbledon a 2-0 half-time lead over the Blues, who are down to 10 men after Josh Harrop was shown a straight red card.
Town made three changes from Saturday’s 0-0 draw with the MK Dons with Harrop, James Norwood and Alan Judge starting and Teddy Bishop and Andre Dozzell dropping to the bench and Armando Dobra from the 18.
The Blues may again start with a four-man backline with Harrop in central midfield ahead of Flynn Downes and Judge on the left and Gwion Edwards on the right. Norwood and Aaron Drinan were up front.
Myles Kenlock, Kane Vincent-Young, Cole Skuse, Tristan Nydam and Troy Parrott were not involved having played for the U23s this afternoon at Playford Road against Barnsley.
Former Blues youngster Shane McLoughlin was on the bench for the home side.
With a small group of Town fans watching from the roof of the new flats under construction behind one of the goals, the game was preceded by a two-minute silence for HRH The Prince Philip, Duke of Edinburgh and the players - again with the exception of Toto Nsiala - taking a knee in support of Black Lives Matter.
In the seventh minute, Ollie Palmer wasn’t far away from getting on the end of a long Nesta Guinness-Walker throw from the left which Tomas Holy gratefully grabbed hold of after Rudoni had seen a shot blocked.
Then at the other end Edwards crossed from the right and Drinan headed against a defender right in front of him.
In the 14th minute Downes broke forward and fed Drinan to his left and the Irishman hit a low shot which Dons keeper Nick Tzanev claimed down to his right.
On 20 Joe Pigott struck a shot from distance which Holy did well to push past the post but form the resultant corner, the home side took the lead. Luke O’Neil sent the ball over from the left and an untracked Nightingale powered a header past Holy. Town boss Paul Cook will have been less than impressed with his side’s defending.
Two minutes later, Tzanev made a mess of a clearance out wide on the left but Edwards’s effort at the empty goal was deflected wide by a sliding defender.
Palmer shot wide on 24 with Rudoni not far away from adding a final touch at the far post but the Dons didn’t have to wait too much longer for their second goal.
"A minute later, O’Neill crossed from the right and Rudoni nodded past Holy from the edge of the six-yard box.
Town’s dreadful start got even worse in the 28th minute when Harrop was shown a straight red card. The midfielder went in late Guinness-Walker, who flew into the air screaming. After taking his time and allowing the defender to be treated, referee Antony Coggins gave Harrop his marching orders, perhaps harshly and more down to the reaction than the tackle itself.
The Blues, who had gone 287 minutes without scoring a goal with 11 men, had given themselves a mountain to climb. They continued with two men up front and a narrow three-man midfield.
In the 34th minute Ayoub Assal burst past Woolfenden on the Wimbledon left before hitting a shot which skipper Luke Chambers blocked.
Four minutes later, Town created a chance to pull a goal back. Edwards picked up another poor Tzanev clearance, this time more centrally. The Welshman took the ball wide before crossing low but just in front of Norwood.
Wimbledon were close to making it 3-0 in the 41st minute when Assal hit a shot on the turn straight at Holy.
That was the last chance of what had been a nightmare half for the Blues in a game manager Cook said would define the season.
Even before the goals, Town had struggled with Wimbledon’s two big men up front, Palmer and Pigott, even before the goals with O’Neil’s crosses also having provided a threat every time they had been allowed to come in.
Both goals will frustrate Cook with the Blues’ defending having been the one positive about the team in his opening matches. As has become familiar, Town presented little threat at the other end even with their full complement.
Even with 11 men Town would appear big outsiders to turn the game around, with 10 it looks an impossibility.
AFC Wimbledon: Tzanev, O'Neill, Woodyard (c), Nightingale, Palmer, Rudoni, Assal, Guinness-Walker, Dobson, Kalambayi, Pigott. Subs: Cox, Csoka, Alexander, Oksanen, McLoughlin, Longman, Osew.
Town: Holy, Woolfenden, Nsiala, Chambers (c), Edwards, Downes, Judge, Ward, Harrop, Norwood, Drinan. Subs: Cornell, McGuinness, Dozzell, Bishop, Bennetts, Sears, Jackson. Referee: Antony Coggins (Bicester).