Glasgow lock Jonny Gray is expected to join Scotland team-mate Stuart Hogg at Exeter Chiefs next season.
Gray, 25, is set to leave Scotstoun when his contract expires at the end of the campaign, with the Premiership leaders his likely destination.
Having lost Hogg, Finn Russell, Josh Strauss and other key players in recent seasons, Warriors will embark on a major recruitment drive for next term.
They have agreed a deal to re-sign Leone Nakarawa until the summer.
The Fiji lock, 31, has been a free agent since being sacked by Racing 92 for returning late from the Rugby World Cup.
Despite being courted by clubs in France and England, he has chosen to return to Glasgow, where he excelled in a three-year stint until 2016.
The off-loading lock was pivotal in Warriors' run to the 2015 Pro12 title - their first and only major honour.
Gray, capped 55 times, was heavily linked with a move to Bristol Bears as his previous deal ran down in 2017, but opted to remain with his home-town club.
A former Warriors co-captain, he has made over 100 appearances in seven years for Dave Rennie's side, and has become renowned for his relentless work-rate and extremely high tackle counts.
Joining Hogg, who left Glasgow at the end of last term, at Sandy Park would offer him the chance to play for Rob Baxter's meticulously built winning machine who have featured in four successive Premiership finals, lifting the trophy in 2017.
Chiefs have won all four of their European Champions Cup matches so far this term, powering past Glasgow in Devon. The Pool 2 leaders visit Glasgow on 11 January.
Gray's departure would leave incoming head coach Danny Wilson a major hole in his pack, with the back-row understood to be an area where the new man is particularly eager to strengthen.