Frank De Boer has warned Jose Mourinho that "karma always strikes back".

The pair exchanged a war of words back in 2017 when De Boer was in charge of Crystal Palace and Mourinho managed Manchester United.

De Boer criticised Mourinho's use of Marcus Rashford, with the Portuguese responding by pointing to his counterpart's poor Premier League record.

Asked about the incident, De Boer told the Guardian: "At that moment, he can say that because it was a really bad record, of course.

"For me, if he wants to say that, I'm not the guy who wants to respond to that … I think karma always strikes back."