Manuel Ugarte gave the ball away near the left touchline and Bilal El Khannouss got to the byline before pulling the ball back to Wilfred Ndidi.
Onana saved Ndidi’s shot with his feet but De Cordova-Reid nodded home from close range.
United’s players traipsed off at half-time to a chorus of boos after failing to manage a shot on target.
Amorim brought on Garnacho at half-time for debutant Patrick Dorgu in a desperate search for inspiration and the Argentina international immediately menaced the Leicester defence.
United’s equaliser came after fine work from the lively Garnacho down the left.
Rasmus Hojlund’s flick from Garnacho’s cross was blocked but Zirkzee tapped into an empty net for just his fifth goal of the season.
United looked the more likely to find a winner but it did not arrive until the 93rd minute, when Maguire headed home from Fernandes’ free-kick.
The England defender appeared to be offside but there was no VAR.
Van Nistelrooy was angry that off-side flag was not raised.
“We deserved to go into extra time, go for the battle in extra time and maybe penalties,” he said.
“Decisions like these in our level are hard to swallow.”
United, 13th in the Premier League, ended the January transfer window lighter than when they started in terms of attacking options after allowing Marcus Rashford and Antony to leave on loan.
Argentine defender Lisandro Martinez was missing after sustaining cruciate ligament damage during last week’s defeat against Crystal Palace.
© 2025 AFP
