Newcastle United will seriously be able to splash the cash this summer – if they sell one of their top stars. It is not an ideal situation, but the Premier League’s profit and sustainability rules mean that selling someone for big money is Newcastle’s best route towards a major rebuild this summer. That is why there is so much speculation over Bruno Guimaraes leaving the club, although it has been reported that the Magpies’ preference is to keep the 26-year-old at St James’ Park. Another mega name who could leave is Alexander Isak. He is Newcastle United’s most expensive signing ever, and is w…