Fletcher, who is no longer contracted to the club but has not announced his retirement, said that as well as improving on D the Skins have to bring in some good prospects in the 2014 Draft.
"We have to draft some players, bring in some more players free agency-wise and hopefully improve and play better defense," he told the club's official website.
"That was really something we didn't do well last year. We didn't play good enough defense as a team."
The free agency begins in March when the season officially moves over to 2014.