The front rower suffered a knee injury in the side's opening match at the Auckland Nines last weekend.
He was ruled out of the remainder of the tournament by Roosters Medical Staff following the injury and yesterday underwent surgery.
It is expected that Isaac's recovery will take 4-6 weeks.
After fracturing his right fibula in the opening minutes of the 2013 Rugby League World Cup Final, RTS has been kept on limited duties throughout the Off-Season and only returned to training in Week 1 of the 2014 schedule.
RTS last week travelled to the Auckland Nines and was monitored by Medical Staff throughout his Rehab program.
It is still expected that he will make a return to play in Round 1 of the 2014 NRL season.
After tearing his ACL in his return from injury, in the Round 15 Holden Cup fixture against the Bulldogs at ANZ Stadium, Tautau underwent a second knee reconstruction in as many seasons.
On a limited working load since suffering the injury, Tautau has responded well to treatment and has returned to running and light training.
It is still expected that he will make a return to play mid-season.