Williams defeated Sevastova in straight sets. Will face Osaka for title.
The two-time US Open champion will face Kei Nishikori next.
The twenty-three time major champion takes a step closer to another US Open title
In a battle of 20-year-olds, Osaka advanced 6-3, 2-6, 6-4.
The defending-champion advanced after a 6-3, 6-3 win.
The Croat is looking to duplicate his 2014 championship run
The Wimbledon finalist advanced past the Canadian 4-6 6-3 6-4 4-6 6-4
The 2016 US Open champion advanced 6-2, 5-7, 6-4
The 2009 US Open Champion is looking to make a return this year