Cousins has been ruled out for Monday's game against the San Antonio Spurs and will be listed as day-to-day moving forward.
The 28-year-old big man sat out down the stretch of Saturday's win over the Oklahoma City Thunder. After the game, head coach Steve Kerr said Cousin "just tweaked" his ankle, according to The Mercury News' Mark Medina.
Cousins has averaged 15.6 points, 7.9 rebounds, 3.6 assists, 1.5 blocks, and 1.3 steals across 21 appearances since making his long-awaited midseason debut. He missed the first 47 games of the campaign recovering from a torn left Achilles tendon suffered last year.
Golden State, now 47-21 overall, is 16-5 with Cousins in the lineup.