Arsenal defender Chambers joins Middlesbrough on loan

LONDON (Reuters) - Arsenal defender Calum Chambers signed for Premier League rivals Middlesbrough on a season-long loan on Tuesday. The 21-year-old joined Arsenal from Southampton in 2014 but has failed to establish a regular first-team place. He has won three England caps. "Calum was the player we were waiting for and he's going to help us a lot," Middlesbrough manager Aitor Karanka said in a statement. Chambers was named last week in the England Under-21 squad to face Norway in next month's Euro 2017 qualifier. (Reporting by Mark Greaves; Editing by Tony Jimenez)