เข่ายันก้าว / Khao Yan Kao
The step-up knee is an advancing knee strike thrown from outside clinch range. Where the clinch knee requires already controlling the opponent, the step-up knee closes the distance with the strike itself, making it a useful entry tool against fighters who try to keep range. The mechanics borrow from the teep: the lead foot steps forward into striking range, the rear knee rises explosively driven by hip drive, and the lead hand can post on the opponent's shoulder or chest to control them at the moment of contact. The step-up knee lands cleanly on the body — solar plexus, liver, or floating ribs — and is particularly punishing against opponents who back up in straight lines. Defensively, the strike commits the fighter forward, so missing it opens you to counter-strikes. It is best used when the opponent's hands are low or when they have just absorbed a strike and are momentarily not loaded for offense.