Sportsmail columnist Martin Keown answered your questions on Thursday ahead of the weekend's Premier League action. Top of the agenda this week was Manchester United's defence. Keown believes that none of the current back four would make any of Sir Alex Ferguson's squads. Also discussed this week is the North London derby and the centre backs who could make a move to the top sides in the Premier League in January. Find out Keown's thoughts on all that, plus the other big clash of the weekend, Liverpool v Everton on Saturday. Email your questions to Martin HERE or send your tweets to @MailSport using #TackleKeown in time for next week's questions.
Manchester United's current defence would not have made any of their teams in the last 20 years . Mario Balotelli has not yet managed to reach the highs of Euro 2012 . Ron Vlaar is not mobile enough to play for either Man United or Arsenal .