One phone call from Chris Davies was all Patrick Roberts needed to convince him to return to the Championship with Birmingham City.

Roberts penned a season-long loan from Sunderland and was one of two deadline day signings Blues made - the other being experienced defender Jack Robinson.

The winger worked with Blues manager Davies briefly at Celtic, when Roberts was an up-and-coming prospect on loan from Manchester City and Davies was Brendan Rodgers' number two.

Now, seven years later, Roberts will play under Davies again.

He told Blues+: "I know the manager, I worked with him when I was younger, so really, one phone call from him was all I needed.

"I was only young when I was at Celtic, him and Brendan Rodgers both helped me and you could see from there how he would take to being a manager.

"I spoke to some of the boys here, they said he's very good and he's come a long way, and he's a top coach."

Roberts is aligned in ambition with everyone inside the building at Blues. Having joined Blues a few months after helping Sunderland win the Championship play-off final, Roberts wants to add another promotion to his CV.

"I didn't take much convincing, it's a big club and getting them back to where they should be was an aim and I'm here to try and help them," he added.

Roberts is a diminutive, left-footed right-winger who should slot seamlessly into Blues' preferred system under Davies.

He has been a fixture in Sunderland's line-up and enjoyed two Championship seasons in which he recorded 10 goal contributions or more.

Explaining his style, Roberts said: "If you ask a lot of people, my biggest strength is probably the teamwork I bring. I show leadership in a different way, I'm very team-oriented and I'm there to help everyone as they would help me. If I can bring goals and assists, that is what I'll do. I want to play on the front foot and get fans excited."