The biggest concern surrounding the San Francisco 49ers' reunion with Robert Saleh is the possibility of him becoming the team's third consecutive one-and-done defensive coordinator.

Robert Saleh cannot personally create turnovers, rush the passer or stop the run. His return as the 49ers’ D-coordinator is no guarantee of success.

Saleh, who was fired in October as the New York Jets head coach five games into his fourth season, generated interest on the head-coaching front and was seen as one of the frontrunners for the Jacksonville Jaguars job. He also interviewed with the Las Vegas Raiders and Dallas Cowboys.