He cracked his weapon its like Zoro not just loses the sword clash his sword gets a crack
No problem dude, it happens, Zoro was pierced in shoulder also by a weaker opponent than him. And his arm(shoulder muscles) are his main source of power, who hold those swords.
I prefer people losing from time to time, if they were only winning every fight, people would complain and call one piece fairy tail.
It seems that even losing some clashes is not enough with some people.
A small crack wound is nothing, anyway, Sanji was fine after the clash.