The Brazilian midfielder, who scored during Spurs' 3-0 win over Cheltenham Town on Saturday, has expressed a desire to leave White Hart Lane.
"I think he'll probably move but it's got to be the right offer. He's looking to move and we'll see what happens this window," Redknapp told Sky Sports News.
"He needs to work harder in training and get fit, but then he's up against [Gareth] Bale and [Aaron] Lennon."
Dos Santos joined Spurs from Barcelona in 2008 for around £5m.