Jose Mourinho and Rafael Benitez have crossed paths, and swords, so many times that even Mrs. Benitez got involved at one point.
"We tidy up his messes," she said in 2015, having seen her husband follow Mourinho at Inter Milan, Real Madrid and Chelsea.
It was meant as a joke. Mourinho, though, did not see the funny side.
"The lady is a bit confused," he responded.
"The only club where her husband replaced me was at Inter Milan, where in six months he destroyed the best team in Europe at the time."
When Manchester United and Newcastle go head-to-head at Old Trafford on Saturday, it will be the latest installment of the Mourinho-Benitez rivalry that has been going on for more than 13 years.