Nacho Novo is out of intensive care after being rushed to hospital in Germany on Saturday.
The Spaniard, 38, was taken ill and had a heart procedure after playing at a tournament for Rangers Legends.
As well as his six years at Ibrox, Novo had spells in Scotland with Raith Rovers, Dundee and Greenock Morton.
Rangers said on Twitter: “Everyone at #RangersFC sends their best wishes to Nacho Novo as he continues to recover in Berlin.”
Novo won seven medals at Ibrox, including three league titles, and also won the Polish Cup with Legia Warsaw.
He also lists Sporting Gijon, Carlisle United, Carolina Railhawks and Glentoran among his former clubs.