Head coach Mike Tice named Winfield and newly acquired free agent Fred Smoot the starting cornerbacks to begin 2005. They started alongside safeties Corey Chavous and Darren Sharper. On November 6, 2005, Winfield collected a season-high 14 combined tackles (11 solo), deflected two passes, and made an interception off Lions’ quarterback Joey Harrington during a 27–14 win against the Detroit Lions in Week 9. In Week 12, Winfield made nine combined tackles, a season-high three pass deflections, and intercepted a pass by Trent Dilfer as the Vikings defeated the Cleveland Browns 24–12.