Sherman had another excellent season in the NFL and was voted as an All-Pro for the second time in as many years, while playing a pivotal role in his side's run to the Super Bowl.
Allen told reporters: "He's extremely bright, in terms of film study and all those things, if you think of all the rules are tilted against you as a defensive player, you have to study film and think about the theory of all the different routes, react in real time, be able to anticipate.
"It's not like Richard is the fastest cornerback or anything else. It's his intelligence that allows him to make all those plays he makes."
Sherman recorded 49 tackles and eight interceptions during the 2013 season.