New Sunderland signing Adam Matthews explains why he needed to leave Celtic this summer

Adam Matthews says he needed to leave Celtic for the sake of his international career.

New Sunderland signing Adam Matthews has told The Scottish Sun that he needed to leave Celtic this summer in order to play more for Wales.

Matthews, 23, had spent four years at Celtic having joined from Cardiff City back in 2011, but left Glasgow over the weekend in order to sign for Sunderland.

The Black Cats confirmed the deal on their official website, luring the Welsh international back to English football on a four-year deal after the Bhoys accepted a £2m bid.

Matthews has now joined up with his team-mates on Wearside, and will be looking to make an impact in the Premier League under former Rangers boss Dick Advocaat.

Days after completing his move, Matthews has now told The Scottish Sun just why he felt he had to move on - and cited that the poor quality of the Scottish Premiership was a factor, as he looks to cement his place in Chris Coleman's Welsh national team.

"The league in Scotland isn’t great and I think the Welsh manager saw that," said Matthews. "Hopefully this move will help me improve my chances of getting into the Welsh team because they’re doing really well."

"I just needed a new challenge. I’ve been at Celtic for four years and enjoyed every minute but I spoke to my agent and it seemed to be a good move for me. I’m happy to move forward and playing in the Premier League was a big factor in my decision - Sunderland are a massive club," he added.

Bad news for Celtic?

Losing Matthews is one thing, but Celtic now have to fear that their other big-name players will read Matthews' comments and follow suit.

Star centre back Virgil van Dijk won't be short of Premier League suitors, whilst midfielder Stefan Johansen could also attract admiring glances after a 13-goal season.

Success in the Champions League could help Celtic keep hold of their prized assets, but the lack of strength in the Scottish Premiership means that Celtic could be fighting a losing battle for some time yet.

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