The Ospreys openside, 21, has been called up to replace George Gasson, who sustained an injury early on in Hamilton last Saturday. Jones was a GB Cadet champion in judo before committing himself to rugby on a full-time basis.
In an unprecedented turn of events, Wales will face series leaders New Zealand first up for the fourth consecutive tournament. Kenya and Fiji complete the pool.
Captain Luke Treharne said: “It’s been a tough week of training leading into Sydney. We identified a few tweaks that need to be made in our game. In sevens it’s such a small margin between scoring and conceding a try, so we’ve been working hard to put them right.
“We’re still learning and developing as a team and looking forward to the challenge this weekend of playing three very good sides.”
Core Players: Luke Treharne (c), Cameron Lewis, Jay Jones, Dafydd Smith, Cai Devine, Will Thomas, Ben Roach Dragons: James Benjamin, Joe Goodchild, James McCarthy Ospreys: Will Jones Pontypridd: Morgan Sieniawski Swansea University: Brandon Wood
Saturday 1st Feb: New Zealand v Wales, 03:31 GMT, Kenya v Wales, 09:05 Sunday 2nd Feb: 02:19.
The World Rugby Sevens Series is broadcast live on Sky Sports, with regular match updates on the competition’s website.