According to PFF (subscription), Indianapolis Colts defensive back Kenny Moore is the league’s top ranked slot cornerback ahead of the 2021 NFL season:
1. KENNY MOORE II, INDIANAPOLIS COLTS
You’ll notice that many of the top slot cornerbacks in the NFL were passed over in the draft before going on to have success. Moore is one such player. He was picked up as an undrafted free agent by the New England Patriots in 2017, only to be cut before making the final roster. Moore landed with the Colts off waivers and has since carved out a valuable role for himself on Indianapolis’ defense.