This placed them too far away to assist Nagumo (and they would have been too slow to keep up with him in any case). Yet, when Nagumo's carriers were sunk, Yamamoto lost an opportunity to salvage something. Carriers, for all their evident potency, were virtually defenseless at night, and Fletcher might have been dealt a crushing blow by Yamato the night of 6–7 June, had Yamamoto stayed closer.[12]