Rhodes extends stay in England
The 28-year-old South African will now remain at the club until 2019.
He impressed in his first season with the Men in Black after joining the north Londoners in 2015 from the Stormers.
Rhodes has made 27 appearances for the Saracens.
"I have thoroughly enjoyed my first year at Sarries, and the decision to extend my stay here really was a no-brainer," said Rhodes.
"Last year was incredible, both on and off the field, as we achieved so much in such a short space of time.
"I have really enjoyed playing in England and in Europe so far, and I'm looking forward to making some more memories alongside some great people."
Saracens Director of Rugby Mark McCall added: "Michael has quickly become a key member of the team since he arrived last summer, and has fitted in to our environment with no trouble at all.
"He is entering his prime as a player, and we are delighted that he has put pen to paper to extend his stay at Allianz Park.
"Alongside a youthful, home-grown core of players, it's great to have the likes of Michael to add to the blend of the group.
"We’re very happy that he is another player who has committed their future to the club."
