James Morrison wants to show Middlesbrough that they were wrong to allow him to leave the club.
The young midfielder joined West Brom for £1.5million in August last year after he was deemed surplus to requirements at the Riverside by manager Gareth Southgate.
Morrison, who came through the ranks on Teesside, believes the experience has helped him to produce the best football of his career.
And the Scotland international is eager to showcase his skills to his former manager when West Brom travel to the North East for Saturday's Premier League clash.
Morrison told the Express and Star: "I don't have any regrets from Middlesbrough other than it being my hometown club and I wish I could have done a bit better.
"But I feel I have something to prove from the point of view that they let me go.
"At the end of the day it is business and they might have thought it was good business. I've come here and I think I had something to prove - to show I have ability and can play at the top level. I'm just starting to do that now.
"Middlesbrough wanted me out to get some money for players. But I don't have any problems with the club.
"I'm not the sort of person to bear grudges. I just let my football do the talking."
There will certainly be a number of familiar faces among the opposition for Morrison, and he has already been in touch with his ex-team-mates ahead of the clash.
He added: "My mates are there who I grew up with in the youth team - hopefully I won't pass them the ball too many times.
"I've been speaking to them a lot this week, having banter and telling them I'm coming for them."