By Simon Mullock & Tom Victor Manchester United manager Erik ten Hag could end up being targeted by Bayer Leverkusen if the Bundesliga leaders lose manager Xabi Alonso to Liverpool. Alonso, 42, has been touted as a replacement for Jurgen Klopp when the German ends his nine-year spell at Anfield at the end of the season. Spain international Alonso spent several years on Liverpool’s books as a player, winning the Champions League in 2005 and reaching the final of the same competition two years later. As revealed by Mirror Football, Ten Hag’s long-term future as United bosscould hinge on how much…