Tennis - Giant killers Bencic and Zhang tumble back to earth

Tennis - Australian Open - Hisense Arena, Melbourne, Australia, January 17, 2018. Luksika Kumkhum of Thailand shakes hands with Belinda Bencic of Switzerland after Kumkhum won their match. REUTERS/Thomas Peter

MELBOURNE (Reuters) - Seed slayers Belinda Bencic and Zhang Shuai were brought back down to earth at the Australian Open on Wednesday as they both failed to follow up their first-round exploits.

Swiss Bencic, who knocked out last year's runner-up Venus Williams on a day of shocks on Monday, slumped to a 6-1 6-3 defeat by Thai qualifier Luksika Kumkhum.