Luffy has used every ability in his arsenal this arc. G5 which he's spammed, ACoC, etc. etc.
And that's besides the point, it actually proves my point anyway. Oda not interested in drawing fights, he just wants us to know oh hey. Kizaru and Luffy stalemate so here's Luffy running out of energy and Kizaru temporarily downed, btw the fight was offpanel here's the last attack. Not to mention Kizaru was not focused on Luffy at all.