Jack Colback has almost certainly played his last game for Newcastle United after a training ground row which has seen him banished from the first-team set-up. Sportsmail understands that the former Sunderland midfielder was already training away from the main group earlier this week when, after one player picked up a knock, he was called to join in. Colback, however, is thought to have refused to take part and this has infuriated manager Rafa Benitez, who has since told the player to train alone. The 27-year-old reported to the club’s training ground on Friday afternoon - after the senior session had finished - and was forced to work by himself.