The two-time league MVP has been bothered by the pain in recent games, so coach Alvin Gentry said it was an easy decision to keep Nash out of Tuesday night's game against the Thunder.
Otherwise, Gentry said, the Suns risk losing Nash for a more extended period of time.
Gentry says Nash played with a lot of pain in Phoenix's 104-88 home win over Sacramento on Sunday night, although the 36-year-old point guard did have 17 assists. It will be the first game Nash has missed this season.
Second-year pro Goran Dragic will start in his place.