In another pulsating match, Spurs raced into a 3-1 lead, were pegged back in the second half by ten-man Leicester, who took a 4-3 lead with just minutes remaining.
But new boy Jermain Defoe smashed home an equaliser in the dying minutes with his fourth goal in three games since arriving from West Ham for £7million.
It was another crazy day with Spurs. They went ahead in the sixth minute when Ian Walker, one of Spurs' former old boys, let in a 25-yard free-kick from Michael Brown at his near post.
But Leicester were level within a minute when Gary Doherty poked the ball past his own keeper Kasey Keller.
Spurs regained the lead five minutes later when Defoe raced onto a throughball by Simon Davies and shot low past Walker.
And in the 27th minute Robbie Keane scored through a crowd of players following a free-kick inside the penalty area when Walker picked up a back pass from Gerry Taggart.
At that stage Spurs looked well in control and could have scored more as Leicester's defence was all at sea.
But the Foxes hit back strongly after the break and scored within six minutes of the restart when an error by Spurs youngster Johnnie Jackson let another old boy, Les Ferdinand, drive a low shot past Keller.
Leicester continued to cause Spurs problems even after Scowcroft's dismissal and Ben Thatcher, yet another former Spur, made it 3-3 in the 72nd minute when he headed home a corner from Steve Guppy.
Five minutes later the incredible happened again as a poor back pass from Doherty allowed Paul Dickov to challenge Keller, and the ball broke for Marcus Bent to shoot home and put Leicester ahead.
But with time running out and two minutes of normal time remaining, Defoe controlled a cross from Ledley King and smashed a left-footed equaliser into the roof of the net.
Tottenham: Keller, Carr, Taricco, Doherty, Richards, Brown (Kanoute 78), King, Davies, Jackson (Anderton 61), Keane, Defoe. Subs Not Used: Burch, Dalmat, Poyet.
Leicester: Walker, Taggart (Davidson 49), Thatcher, Dabizas, Nalis, Guppy, Scimeca, Freund, Ferdinand (Bent 78), Scowcroft, Dickov (Sinclair 86). Subs Not Used: Coyne, Stewart.
Sent Off: Scowcroft (70). Booked: Taggart, Dabizas.
Attendance: 35,218
Referee: N Barry (N Lincolnshire)