By Jamie Spencer Manchester United manager Erik ten Hag has given a clear indication that Casemiro won’t leave the club before the end of the summer transfer window. Casemiro’s future at Old Trafford had been put in some doubt amid persistent links with a switch to the Saudi Pro League. He also struggled in the closing stages of last season, notably during a shock 4-0 defeat to Crystal Palace in April, having earlier missed a big chunk of the campaign injured. But with defenders back fit, Ten Hag was able to get the veteran Brazilian back in midfield for Saturday’s Community Shield against Man…