"Post kvar periodoj, ni gajnis."
Translation:After four periods, we won.
If there were 9, you couldn't win after 4. (Baseball requires at least 4 1/2 innings with the home team ahead for a complete game in case of rain delay.) If there was 4, you wouldn't bother saying "after four periods" since that is the normal result.
So it's most likely 3 periods with a single overtime period (ice hockey) or 2 periods with an overtime of two 15-minute periods (soccer (association football)).