Conor Gallagher came on as a substitute as Atletico Madrid secured a dramatic 90th-minute winner against RB Leipzig in their Champions League opener.
The German side took an early lead in the fourth minute through Benjamin Sesko’s header, but Antoine Griezmann equalized in the 28th minute with his 37th Champions League goal, a volley from 12 yards out.
Griezmann was later denied a second by a fine save from RB Leipzig goalkeeper Peter Gulacsi.
In the dying moments, Griezmann delivered a crucial cross, which José María Giménez converted with a powerful downward header for the win.
Gallagher, who joined Atletico for around £33 million in August, entered the match in the 63rd minute when the score was 1-1.
He became the second English player to represent Atletico in the Champions League, following Kieran Trippier.
RB Leipzig will face Juventus next on October 2, while Atletico Madrid travel to Benfica the same day.