Ex-Celtic favourite reveals the key Parkhead connection that played vital role in deadline day move

The 28-year-old has spent the last three-and-half seasons with Sunderland, playing an essential part of the Black Cats' starting XI that climbed all the way from the third tier to the English Premier League, playing 147 times across all competitions, scoring nine goals and assisting a further 18.

However, his time with Regis Le Bris’ side looks to have come to an end after he opted to make a season-long loan move to St Andrew’s in the final hours of the transfer window, where he’ll play alongside former Hoops men Kyogo Furuhashi and Tomoki Iwata.

“I’m a winner,” said Roberts. “This is a place, and a club, that wants to strive to get to the top. Off the back of last season, where I did that [winning promotion], I can see there’s potential here to have a good season. It didn’t take much convincing. It’s a big club, and getting back to where Birmingham should be is an aim.

“Doing what the club did last season [winning EFL League One with a record points haul] is no small feat. It’s a hard league, I’ve played in it myself, so to go and get the points record is something special. To join now is exciting, there’s a lot of momentum, and it’s a huge club.”

Roberts, who won three Scottish Premiership titles, two Scottish Cups, and two Scottish League Cups at Celtic after joining from Manchester City on a two-and-a-half year loan spell, had been inked with a move to La Liga earlier in the summer, according to a report from the Sunderland Echo. The tricky winger turned down opportunities to leave the Stadium of Light in recent weeks in order to fight for his place on Wearside.

However, the player himself admits the opportunity to move to the Blues was too good to turn down, revealing it was a special connection with current Birmingham manager - and former Celtic assistant - Chris Davies that sealed the deal for him, recalling his memories of the duo working together during Roberts’ time on loan in Glasgow.

“I know the manager,” said Roberts. “I used to work with him a few years ago when I was younger [Celtic]. One phone call with him was all I needed. I'm looking forward and getting started. He was a huge influence. I was only young when I was at Celtic; he and Brendan Rodgers at the time both helped me.

“You could see from there how he would take to being a manager. I spoke to some of the boys here, who said he has come a long way and is a top coach. I kind of already knew that, but speaking with him, the way he is as a person, it was great just to have a chat with him, having not spoken for a while, just about how enormous this club is, and what I can bring to this club was a huge [in the move] as well. It didn't take much to persuade me, but we had a good relationship [at Celtic] and hopefully we can continue that here as well.”

Sign up to The Scotsman’s daily football newsletter to get unrivalled Scottish football news and analysis - subscribe for free here.