Paul Casey has used a sponsorship exemption to enter the field for the Singapore Classic to mark his first return to the DP World Tour since he joined LIV Golf. The 46-year-old is one of the most successful players in DP World Tour history having won 15 times in his career – just two less than Rory McIlroy. But he packed in his European tour card to join LIV Golf in the summer of 2022 and he hasn’t been back since. Casey took a swipe at the DP World Tour for ‘changing the goal posts’ when players were fined for playing on the LIV Golf series shortly after he signed for LIV Golf. “What happened…