Jordan Ayew's added-time equalizer denied Ipswich the first goal first division victory of the season as Leicester earned a 1-1 draw.
Ipswich were on course for their first three points in the top flight since April 2002 when a superb volley from Leif Davis put them ahead. But the hosts saw Kalvin Phillips sent off with 13 minutes remaining and the 10 men could not hold on. Ayew's last-gasp goal meant Kieran McKenna's immensely watchable side have blown a lead five times in 10 league games this season.
Leicester, with their coach Steve Cooper serving a touchline penalty, should have taken the lead in the third minute when Jamie Vardy got in behind Ipswich's back four. But the 37-year-old opted to square the ball rather than shoot and Stephy Mavididi botched his shot.
Moments later, Leicester almost gave the hosts a goal when Jannik Vestergaard miscontrolled a pass from goalkeeper Mads Hermansen. Omari Hutchinson took the ball from the defender and lifted an inviting cross for Sam Szmodics, who headed in vain.
Facundo Buonanotte, on loan at Leicester from Brighton, embarked on a labyrinthine run towards the penalty area, beating four players before Arijanet Muric saved his deflected shot.
After half an hour, Dara O'Shea found a Davis corner unmarked at the far post, but the Ipswich defender planted his header on the ground and wide. Ipswich, however, were playing some eye-catching stuff, and Liam Delap's flamboyant pass was collected by Conor Chaplin, who deflected inches wide of the far post.
Hermansen had to come out bravely to fend off Delap's onslaught and then hold off Ben Johnson's advance with Ipswich, as so often this season, unable to convert some wonderful chances into goals.
That changed nine minutes into the second half when Davis scored with a beautiful volley from the far post. The left-back received a cross from Sam Morsy with a measured, cushioned effort that beat Hermansen and inside the far post.
The atmosphere inside Portman Road changed after a chaotic couple of minutes. First Chaplin was brought down by Abdul Fatawu in the box, but referee Tim Robinson dismissed Ipswich's penalty appeals. Robinson then angered the home side even more when he showed Phillips a second yellow card for a foul on Fatawu.
Leicester sensed their chance, but Buonanotte fired from 15 yards and Ayew's shot was saved by Cameron Burgess.
However, in the fourth minute of added time, Morsy was dispossessed by Boubakary Soumaré. Soumaré fed fellow substitute Ayew, who played a good one-two with Vardy before sliding the ball under Muric to leave Cooper celebrating from the press seats and Ipswich completely dejected.