One of the three investors in Dave Checketts’ purchase of the Blues and the Savvis Center lease has backed out of the deal, multiple sources have told the Post-Dispatch. After announcing a purchase agreement with Blues owners Bill and Nancy Laurie March 22, Sports Capital Partners and Towerbrook Capital Partners will continue with their plan to buy the hockey team and arena lease. But they will do so without EchoStar Communications Corp., a third investor that had gone unnamed until now. ...Multiple sources said that EchoStar brought value to Checketts’ purchase group, but SCP and Towerbrook were not depending on the company to complete the transaction. Checketts, who was not available for comment Wednesday, had a Plan B in place, those sources said.