Jack Grealish has sent Mateo Kovacic a one-word message after his goal for Manchester City in their 5-1 win against Luton Town. Kovacic’s goal gave City their much-needed two-goal cushion, as he scored his first goal for the club in the Premier League. The 29-year-old had scored twice for Pep Guardiola’s men in the past, once against Urawa Red Diamonds in the FIFA Club World Cup and the second against Luton in the FA Cup. On both occasions against Rob Edwards’ side, the Croatian international has managed to score an absolute belter. In his side’s latest outing, the £30 million man got on the e…