Everton under-18s beat Manchester City in the fourth round of the FA Youth Cup on Saturday thanks to a sensational 97th-minute winner from midfielder Luke Butterfield.
But the result was dampened by a potentially serious injury suffered by Tyler Onyango, with the 18-year-old being stretchered off in the second-half after a dangerous tackle by Alex Robertson.
Robertson apologised to Everton players as Onyango was removed from the field and the extent of the damage will be assessed by club officials.
Goalkeeper Zan-Luk Leban, a Slovenian youth international, kept Everton in the game with a string of fine saves including a double stop in the second period.
Lewis Warrington - who owns an Everton season-ticket at Goodison Park - also impressed as City dominated for large periods.
The Citizens named Liam Delap in their starting line-up, with the striker having already made his Premier League debut under Pep Guardiola, but he was kept at bay by the sensational Leban.
And with seven minutes of additional time played due to the injury suffered by Onyango, Butterfield hit a sumptuous half-volley with his left foot that found the bottom corner from outside the area.
Everton are currently scheduled to travel to Chelsea in the fifth round on Saturday 17 April.
