Free agent Kellen Winslow pleaded not guilty Thursday to a charge of synthetic marijuana possession. The arrest occurred in November when a woman called police alleging she saw Winslow masturbating in his vehicle in a Target parking lot. Police didn't charge Winslow with lewdness, but did perform a search and discovered the synthetic weed. He'll have a hearing on March 13. Winslow told officers he had synthetic marijuana "because the NFL tests players for actual marijuana."