Things really heat up at Flushing Meadows on Labor Day, as spots in the quarterfinal in the season's final major tournament are at stake in both the men's and women's draw.

No. 1 Roger Federer takes on American Mardy Fish, who is ranked 23rd in the final match of the day session at Arthur Ashe. The matchup is sure to be the top-seed's toughest test to date, as Federer has yet to drop a set at the U.S. Open. Fish outlasted No. 23 Gilles Simon in the third round in four sets to reach the showdown with Federer.

Joining Federer during the day session will be No. 4 Serena Williams, whose fourth-round opponent Andrea Hlavackova, is unranked. A showdown on Louis Armstrong between No. 11 Nicolas Almagro and No. 6 Tomas Berdych will be the day's closest meeting of ranked opponents in either draw.

No. 3 Andy Murray will be tested during the night session against No. 15 Milos Raonic.

For a full schedule of the day's matches, check out USOpen.org. For live streaming video, check out U.S. Open Live.

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