Andy Gray has warned one Manchester City star he could suffer a fall from grace similar to Manchester United’s Marcus Rashford if he’s not careful. Rashford has caused controversy in recent weeks after he missed a training session ahead of United’s FA Cup tie with Newport County. The striker was fined two-weeks’ wages and the matter is now closed but that doesn’t change the fact his form has dropped considerably after his best-ever goal return of 30 last season. Rashford has scored just five times so far in the current campaign and pundit Gray thinks City’s Jack Grealish is in danger of headin…