Both managers were full of praise for striker Darren Bent after his brace helped Sunderland secure a 3-1 victory at home to Birmingham City.
The 26-year-old England international has now scored 21 goals this season, having joined the Black Cats from Tottenham Hotspur in the summer.
Home boss Steve Bruce commented: "He has done fantastically for Sunderland and he is worth every penny.
"It just shows you that a bit of quality, playing every week, he has flourished with the chances we have given him. He has been terrific.
"Where would we be without him, but that's the difference.
"You pay £10million, £12million - he will probably end up costing us £14million or whatever it is, but that's the difference. It's the next step."
Beaten Blues manager Alex McLeish added: "He's a handful. He is quick, he is exceptional, but you have got to hand it to him on his finishing, because you can have all the speed in the world and not be a good finisher.
"Twenty-one goals is a fantastic return and he looks a real threat. But I feel my defenders will look at it and feel they made it too easy for him."