Three short lines, and a whole scene opens up. The title, "Postseason," tells us the baseball year is over, and the poem shows what is left: an empty ballfield, and at home plate, where players once stood and crowds watched, only a rabbit.
The speaker doesn't say how they feel, but the feeling sits in the picture. There's a quiet sense of absence, the way a place seems bigger and stranger once the noise has gone. The words "late in the fall" add a note of ending, since the season is over and the year is closing too. Still, the mood isn't bleak. A rabbit sitting calmly on the most important spot on the field is a little funny and a little tender. Nature has simply moved back in.
The poem works by leaving things out. We're left to imagine the cheering that isn't there, and to notice how easily a place goes back to being wild and still.