Manchester United face their biggest test of the Ralf Rangnick era on Wednesday night against Champions League specialists Atletico Madrid.
Diego Simeone's team are renowned for their defensive capabilities but will also create chances to service a wealth of attacking talent that includes Luis Suarez, Joao Felix and Antoine Griezmann.
When those chances do happen, and they will due to United's ongoing defensive vulnerability, it will be up to David de Gea to save the day.