Paul Warne must fix one alarming problem at Derby County to keep his side in the Championship next season. Derby earned promotion back to the second tier with a 2-0 win over Carlisle United last month, sparking scenes of jubilation at Pride Park. Some of the first-team squad have since enjoyed a trip to Las Vegas while Paul Warne has continued his plans for next season. The Rams announced they’d be releasing six players from their contracts in June, with Conor Hourihane, Korey Smith, Martyn Waghorn, Scott Loach, Dwight Gayle and Joe Wildsmith all told to leave the club. Warne has let go of som…