News of the proposed switch has been met with surprise, but Redknapp believes that the 32-year-old is deserving of a chance with his boyhood club.
"The role that he will have is to bring people into play and he plays in a very modern Southampton side. He likes freedom and is not just one of those centre-forwards that stands up front. He's a lovely link player and I think he deserves this opportunity," Redknapp told Sky Sports News.
Lambert scored 14 goals in all competitions for the Saints last season.