Carmarthen born Priestland, who turns 28 in three days time, played a pivotal part in Scarlets' 22-10 victory over Ospreys at Parc y Scarlets on Saturday evening and will now focus on the remainder of his season at Parc y Scarlets with a top of the pool clash against reigning European champions Toulon next in the region's sights.
A career Scarlet and a shining example of the region's ethos and success in developing homegrown talent, Priestland joined the senior environment at the region aged 18, in 2004, having played for Llandeilo RFC and Carmarthen Athletic. He represented Wales Under 19s and Under 20s before winning his first senior international cap during the 2011 Six Nations campaign in the 24-6 victory over Scotland. He established himself as Wales' first choice outside half at the 2011 Rugby World Cup and has 32 caps.
Since making his competitive debut in Scarlets colours in September 2007 the unassuming fly half has gone on to make 147 appearance for the region amassing a current total of 1059 points - just six points away from breaking Stephen Jones' regional record and becoming the highest scoring Scarlet in regional history. He has been a part of some historical victories in his ten-year tenure at the region.
Scarlets Head Coach Wayne Pivac said: "We are disappointed to see Rhys go, he's been a big part of the region for a long period of time and is a true professional both on and off the field. We appreciate that this is a great opportunity for Rhys to further develop and progress on a personal level.
"As a region we were keen to retain Rhys' services but were unable to do so. Despite our desire and commitment to retain all of our international players within the region there are times when it's not the right decision for the individual player at the time.
"Rhys has developed into a skilled fly half who commands excellence at all times and his leadership qualities, experience and maturity will be missed.
"This is an exciting new challenge for Rhys; he goes with our blessing and he will always be a Scarlet. He has been a great servant and we wish him well with his future."
Speaking about his decision to leave his region of origin Rhys Priestland said: "I have thoroughly enjoyed my time here at the Scarlets; there have been some great highs and some heartfelt lows.
"It's a huge privilege to have played with some of the players I have during my time here with the Scarlets.
"I have been lucky to have been involved in some fantastic fixtures and career highlights here at the Scarlets would have to include representing the region in the Heineken Cup over the years.
"The Scarlets has been my home for a number of years and all that I've known as a club as a senior professional player. I will certainly miss the place and will be leaving some great friends behind but there's a long way to go this season. I just enjoy playing for this team. It's my home region and every time I pull on the shirt it's an honour.
"I will be fully committed to helping the team achieve the ambitions we have set ourselves at the start of the season. Hopefully it can keep on improving for me personally and as team for the rest of the season."
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