Defoe is yet to score in the Premier League this season.
"Defoe has an injury again. He's had a problem with his ankle before and it didn't feel too good," Redknapp said in Dubai-based newspaper The National.
"We're trying to finish in the top four and it's so close. But we've got so many players injured, people forget.
"If you could pick a team of injured players it would be a fantastic team."