But they could return in time for the Rugby Championship.
Stormers coach Allister Coetzee yesterday confirmed both De Villiers and Etzebeth has been ruled out of the remaining two games – against the Bulls this weekend and the Sharks next weekend, both at Newlands.
Etzebeth, having made his way back from an ankle injury, suffered a new setback in the form of a broken toe which will keep him out of action for another two to three weeks.
De Villiers (knee) has been ruled out for another four weeks with both he and Etzebeth having missed the four June Tests.
They could be faced with a race against time for the Championship opener against Argentina at Loftus on August 16.
The Stormers will also be still without Damian de Allende who, like De Villiers, will miss the next four weeks due to a knee injury.
In more positive news flank/hooker Deon Fourie (concussion), hooker Tiaan Liebenberg (neck), scrumhalf Louis Schreuder (broken thumb), centre Juan de Jongh (pneumonia), wing Kobus van Wyk (wrist) and fullback Gio Aplon (elbow) are all back in full training.
But they will still be without their four top props, with Brok Harris (AC joint) undergoing surgery. He is out of action until late August, while Oli Kebble (ankle – syndesmosis) is only due back in late August or early September.
According to the Stormers medical report, Bok Frans Malherbe (concussion) is making good progress after showing symptoms for some time but should return for the Absa Currie Cup competition, while Steven Kitshoff (knee and ankle injuries) will not play again this season.
Hooker Scarra Ntubeni (broken foot) will be available for the first round of the Currie Cup competition.