Let me elaborate on that question. The way I understand grammar, it should be direct object (or accusative) instead:

  $ball = new Ball:Soccer;  # Creates a soccer ball. 
  kick $ball;               # Ball::Soccer defines sub kick {...}
                            # I.E. this reads $ball->kick;
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We can easily defend that in this example, $ball is not a subject ("it performs the action expressed by the verb"). Rather it could be argued that it is a direct object ("Entity acted upon", I.E. the action is to kick, the thing which is kicked is the ball). Also:

One rule of thumb for English, however, is that an indirect object is not present unless a direct object is also present

— Wikipedia: Object (grammar) - Types of objects

For a dative case to be present, we'd need something like

$ball = new Ball::Soccer;
$john = new Person;
give $john $ball;
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And even here, $ball would still be the direct object, or accusative (the object which is being given) and $john would be the indirect object, or dative (the object to which (or rather whom) the ball is being given).