Ferdinand, who has regular contact with Defoe in his role as Tottenham's forwards coach, thinks the 28-year-old will soon be among the goals.
"People have talked about Jermain Defoe not scoring many goals this season but he was out for three months," Ferdinand told Sky Sports News.
"He struggled to find his groove again like Wayne Rooney struggled for most of the season, then all of a sudden he scored and went on a run. That's what happens to strikers.
"There is a lot of rotation going on these days so players are in and out of the side and they are looking for that level of consistency and once you get that first goal you tend to go on a run."