The 23-year-old helped Wales to win the Grand Slam in the Guinness Six Nations last week and scored three tries during the tournament, including efforts against England and Scotland.
“It is great to be returning to Wales and I cannot wait to link up with Cardiff Blues next season,” he said on Cardiff Blues’ website.
“It is a young and exciting squad, with a good blend of experience, which has a bright future and I’m looking forward to contributing towards that.
“I will always be grateful to Worcester Warriors for giving me the opportunity to become a professional player and I have loved my time at Sixways.
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“But to play for Wales I need to play in Wales and Cardiff Blues is the best fit for me. I’m really looking forward to the next chapter at Cardiff Arms Park.”
Adams was the Premiership’s joint-top scorer last season with 13 tries, but Cardiff head coach John Mulvihill is confident he can further develop his potential and match the Welsh club’s own drive for success.
“It’s an exciting signing for the region and demonstrates our strong rugby ambition going forward,” Mulvihill said.
— Cardiff Blues (@cardiff_blues) March 19, 2019
“Josh is a player we can build success around. He brings genuine hunger to succeed, enormous energy and the skill-set and speed to make a real difference to our group.
“Just from watching the Six Nations, you can see he’s a really busy player, who makes big contributions both in attack and defence, and is a good team man.
“We’re looking forward to getting him on board for next season.”
Adams decision to join Cardiff came on the same Tuesday that regional rivals Scarlets were boosted by their Slam-winning trio – Jonathan Davies, Ken Owens and Rob Evans – signing contract extensions to stay at Parc Y Scarlets.
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