Serena Williams: Shaking Off Loss ... And Nearly Her Top

Even when Serena Williams loses on the court, her body still dominates off it -- exhibit A was spilling out of her shirt Wednesday night in L.A.

Serena hit up celeb hotspot The Nice Guy in a severely buttoned-down shirt ... showing off most of her black bra and a ton of cleavage.

While she might still be stinging from that Australian Open loss last weekend, this should help Serena's fans recover.