Ivan Toney will have a "burning desire" to prove Newcastle United wrong if he gets the chance to star in the League Cup quarter-final for Brentford on Tuesday night.
The Magpies sold Toney to Peterborough in 2018 after a series of loan spells at places like Scunthorpe, Wigan and Barnsley before the Bees paid £5million for his services last summer.
Toney had netted 49 goals in two years for Posh and has hit the ground running at Brentford with 16 in 20 Championship matches for Brentford after replacing Ollie Watkins who signed for Aston Villa in a £33million deal.
Bruce said: "He's done very well. He had the biggest disappointment of all with being rejected.
"It looks like he's playing with that burning desire to prove people wrong.
"You have to say well done to him.
"He will be a threat because he's playing with a lot of confidence.
"He will want to do his utmost to prove people wrong for letting him go."
Bruce has also revealed he went on a personal scouting mission to see Brentford play live in the Championship two weeks ago.
He said: "I went to see them two weeks ago and they are a good side.
"They have been a good side for the best part of three or four years."
