Black Cats boss Martin OâNeill called his old friend before the deal went through and asked for his opinion on the Scottish striker.
McCarthy told the Sunday Sun: âMartin had left Celtic by the time Steven made the breakthrough up in Scotland with Hibs, so he really did not know him as a person.
âMartin asked for my opinion and I gave it. I will be honest with you; I waxed lyrically about Fletch.
âAll I told Martin was that he was a brilliant professional and a great person.
âThe lad was a joy to work with. I have not a bad word to say about him.â