Moto2 rider Stefano Manzi will make his WorldSSP debut at Jerez this weekend as he replaces the injured Andy Verdoia.
GMT94 Yamaha have already been through several rider changes this season after starting with Jules Cluzel and Federico Caricasulo.
The Frenchman remains part of the team although injured at present, while Caricasulo has since moved to the Biblion Iberica Yamaha Motoxracing team.
Other riders such as Valentino Debise, the above-mentioned Verdoia, Dani Valle, Patrick Hobelsberger and Ludovic Cauchi have all raced for the team so far in 2021.
Manzi currently rides a Kalex machine in Moto2 but will make a switch to the much favoured Yamaha R6 as it relates to the Supersport class.
The Italian added: "I am delighted to be taking part in the WorldSSP round in Jerez with GMT94. They are one of the best teams in the championship.
"I am looking forward to riding the Yamaha R6 in WorldSSP configuration, as I am used to training on a stock R6.
"There are some differences, but we can do well with the GMT94 team."
Manzi has just two top ten finishes in Moto2 this season - Qatar (2) and Mugello, and is without points in any of the last five rounds.
Still, that hasn’t stopped Team Manager, Christophe Guyot from expressing his excitement at having the Italian: "We are glad to welcome Stefano to our team. He comes from Moto2 where he has already made some great moves.
"He knows the Jerez circuit well, as well as the Yamaha R6. He is very keen to join the team and to participate in this event.
"So he has all the ingredients to adapt to the GMT94 Yamaha R6 which will get the number 62."