Losing likely Hall of Fame receiver Calvin Johnson to retirement is a blow to Stafford 's fantasy potential .
Receiver 's still a pretty safe bet for 4,000 - plus yards and 30 or more touchdown passes .
Losing likely Hall of Fame receiver Calvin Johnson to retirement is a blow to Stafford 's fantasy potential , but he 's still a pretty safe bet for 4,000 - plus yards and 30 or more touchdown passes .