The Blues were 13th in the Western Conference with 65 points, seven points out of the final playoff spot. Before Monday's deal, St. Louis unloaded forward Brad Boyes to Buffalo, and defensemen Eric Brewer and Erik Johnson to Tampa Bay and Colorado, respectively. Brewer had been team captain.
The 29-year-old Winchester, a checking forward, had nine goals, 14 points and 86 penalty minutes in 57 games with St. Louis.
The Blues recalled forwards Chris Porter and Ryan Reaves from Peoria of the AHL and placed forward Philip McRae on the injured list.