Tenacity
Wow. Kobe Bryant scored 81 points against the Raptors just very recently. This is to date, the second highest ever production in NBA history. Wilt of course still holds that hundred point production for the number one spot, still. (I have a theory, all sports records will soon fall, sooner or later. Wilt's record would probably fall by the wayside in year 3000, if ever basketball is still alive by then.)
Going back to Bryant, to say that he was on fire in that game is an understatement. That is of course basketball skill, that is of course excellence, that is of course showmanship, that is of course playing in his innermost zone. More than all those, there is just one word that would define his performance on that record-setting game: TENACITY.