He initially caught the eye at Ajax before his switch to Celta Vigo in Spain and then hitting the goal trail in his time at Porto - his goals helped Porto knock Manchester United out of the Champions League in 2003-04.
Mido and McCarthy were together for a short period at Celta Vigo at the end of the 2002-03 season and Mido is far from surprised that the 29-year-old has done well in the Premiership.
"Benni is a player with a lot of character, a very good striker with a very good finish and we'll have to watch him," said Mido.
"He's a good friend of mine and I was very happy for him when I heard he'd signed for Blackburn. I spoke to him and I knew he would be able to cope and he's done fantastically well there.
"It takes a good mentality to move to the Premiership and he's adapated well, hopefully he'll score plenty more goals - but not against us!"
Mido pinpoints his former team-mate Benni McCarthy as one to watch in the Blackburn ranks as we face Rovers at Ewood Park on Sunday.The South African hitman has scored seven goals in 17 starts in all competiitons, four in the Premiership, since moving to Lancashire from Porto in the summer.