Coco Gauff, the youngest player at the Australian Open, made it to the fourth round in her biggest performance yet. The 15-year-old ousted defending Japanese champ Naomi Osaka. Meantime, Serena Williams' quest for a 24th Grand Slam singles title at the Open is over. She suffered a shocking upset to China's Wang Qiang, marking her earliest exit at Melbourne Park in 14 years. Watch "CBS This Morning" HERE: http://bit.ly/1T88yAR Download the CBS News app on iOS HERE: https://apple.co/1tRNnUy Download the CBS News app on Android HERE: https://bit.ly/1IcphuX Like "CBS This Morning" on Facebook HERE: http://on.fb.me/1LhtdvI Follow "CBS This Morning" on Twitter HERE: http://bit.ly/1Xj5W3p Follow "CBS This Morning" on Instagram HERE: http://bit.ly/1Q7NGnY Get new episodes of shows you love across devices the next day, stream local news live, and watch full seasons of CBS fan favorites anytime, anywhere with CBS All Access. Try it free! http://bit.ly/1OQA29B Each weekday morning, "CBS This Morning" co-hosts Gayle King, Anthony Mason and Tony Dokoupil deliver two hours of original reporting, breaking news and top-level newsmaker interviews in an engaging and informative format that challenges the norm in network morning news programs. The broadcast has earned a prestigious Peabody Award, a Polk Award, four News & Documentary Emmys, three Daytime Emmys and the 2017 Edward R. Murrow Award for Best Newscast. The broadcast was also honored with an Alfred I. duPont-Columbia Award as part of CBS News division-wide coverage of the shootings at Sandy Hook Elementary School in Newtown, Connecticut. Check local listings for "CBS This Morning" broadcast times.