Lambert, 21, has signed a two-year deal with the NSW Waratahs ahead of their 2023 Super Rugby Pacific campaign.
It is something of a homecoming for the loosehead who was born in Sydney and was part of the Waratahs Academy before heading to Scotland in 2020.
Lambert, a former Australian Schools international, switched allegiance and played for Scotland in the 2020 U20 Six Nations. He signed for Glasgow Warriors on an academy contract before graduating to the main team in 2021. He made five appearances in the Rainbow Cup last year, but saw his progress hampered by an ankle injury and was one of seven players released by Glasgow at the end of the season.
Lambert felt the move to Scotland was beneficial for his development but was delighted to return to the Waratahs.
“It’s a bit surreal for me to come back and sign for the Waratahs,” Lambert told the Sydney club’s website.
“I was in the Academy here when I left school but made the move to Glasgow to gain some experience abroad and play for the Scotland U20’s side and with the Warriors in the United Rugby Championship.
“The move abroad was great for my rugby development, especially my set piece, and something I hope can benefit the team.
“Being born in NSW, I always aspired to come back and play for the Waratahs so I’m extremely grateful for the opportunity and cannot wait to rip in.”
Lambert is the latest of the Glasgow leavers to find a new club. Rob Harley, who holds the record for most Warriors appearances, has moved to France to join the Pro D2 side US Carcassonne; lock Kiran McDonald was signed by Gallagher Premiership team Wasps; Scotland international hooker Grant Stewart was snapped up by Connacht on a short-term deal; lock Hamish Bain has moved to English Championship side Jersey Reds and prop Ewan McQuillin has signed for Selkirk. Robbie Fergusson is back in the Scotland Sevens set-up and was part of the squad for the recent Commonwealth Games.