As expected, Arsene Wenger shook things up in the team selection for his 750th game at the helm, naming an entirely different starting XI from the one which let a 2-0 lead slip at West Ham in the Premier League on Sunday.

Former Barcelona trainee Merida drilled in a fine first-half strike as Wenger’s faith in youth was once again justified.

The 19-year-old collected a loose ball before unleashing a rocket from 20-yards that beat Diego Cavalieri at his near post.

Nicklas Bendtner, himself only 21 but now a regular in the side, then produced a powerful finish after 50 minutes to put Arsenal into the last eight after Emiliano Insua (26) had equalised with a spectacular strike of his own.