The Gilas Pilipinas guard suffered a sprained right ankle on Sunday in the team's 99-84 defeat to the Kyoto Hannaryz in their Japan B.League encounter.
Ramos had 11 points, six rebounds, and four assists before he had a bad fall that led to the injury.
The team has yet to make an annoucement on Ramos' status.
Hokkaido holds a 3-8 win-loss record.
Ramos, in his second season in Japan, is averaging 12.2 points, 4.6 rebounds, 4.0 assists, and 2.4 steals in 27 minutes through 11 games.