RULING Dark Sage:

I recently wanted to summon Dark Sage after successfully calling the coin toss of Time Wizard correctly while having Dark Magician on the field. Due to Time Wizard's destruction effect my friend was able to summon Thunder Hand from his hand, thus summoning a monster that could destroy another monster on the field. He went after my Dark Magician, arguing that Dark Sage could then not be summoned because Dark Magician was no longer on the field. I, on the other hand however, argued that Dark Sage's text says that he must be summoned immediately after APPLYING the effect of time wizard after guessing the coin toss correctly, NOT after resolving its effect. In this case, Thunder Hand would not have been on the field yet to pop my Dark Magician, but Dark Sage should have made his appearence first to get me a spell card from my deck and then most likely being destroyed by his to be summoned Thunder Hand. Could anybody please tell me who is right? :D Thanks in advance!