The 28-year-old Blommetjies was released by Scarlets after being with the Welsh side for one season after joining from the Cheetahs.
He failed to make an impact with the Scarlets and played in just six matches before being loaned out to English side Leicester Tigers.
Former Scarlets boss Wayne Pivac was not happy with Blommetjies’ fitness levels.
“We do things a bit differently from the Cheetahs and expectation on the players is to be in a certain shape and Clayton has a bit of work to do in that area,” Pivac said at the start of last season.
The Free State Cheetahs open their tournament with a challenging fixture against the Blue Bulls at Loftus Versfeld on Friday, July 19.
Blommetjies came through the ranks at the Bulls, playing all his junior rugby there, and later at the age of 20, made his senior debut in the Currie Cup. He has become an integral part of the Cheetahs side with many of their successes attributed to his play.
Paarl born Blommetjies made an impact in his debut Guinness PRO14 season scoring four tries, making five try assists and features in the top five for metres gained.
However he has failed to impress during his stint in European rugby.
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