Chelsea boss Jose Mourinho has defended Asmir Begovic after a bumbling debut in defeat to New York Red Bulls.

Begovic had a nightmare start after coming on for the second-half for Thibaut Courtois, as Chelsea endured a calamitous period in which they conceded four goals including one scored by a 16-year-old high school kid, Tyler Adams, in a performance which Mourinho labelled a "disaster".

Mourinho said: "First of all I think he was tired, the same as Thibaut Courtois and when goalkeeper are very tired, co-ordination is low, agility doesn't exist, speed reaction doesn't exist.

"Courtois made a mistake in the first half on his feet; Begovic in the second half was not sharp in his reactions. So, for me it is a consequence of that. But he is fantastic goalkeeper, no problem.

"I'm so happy to have him. Next game against Paris St Germain he will start and play the first-half so no problem. It's just a process."