Thanks for answering, but Xin Rong, without a weapon, subdued Spike, In the explosion, the slayer lost the opportunity to stake, Spike injured Xin hands and I suspect also his foot, the foot he used to subdue Spike.

Spike is a character has mental agility is quick to think.

a similar case when Buffy was staked with his own stake (5x07), Buffy overconfident or the vampire was more ingenious other case Buffy and Spike first battle, Spike almost impaled Buffy but Joy saved Buffy.

Combat skill is determined by the effectiveness of attack, defense, evade. Dana an inexperienced slayer without training, with only her instinct to fight, gave Spike and Angel problems.

In my opinion, She lost the battle because of other circumstances, not because his combat technique was not good enough. I see his combat technique as effective, I don't see unarmed martial arts in a lesser degree.

Spike is a clever and cunning vampire and is stronger than a regular vampire, he is not as strong as a slayer, but he is quick to think and improvise.