ATP roundup: Frances Tiafoe advances in Washington

(Photo credit: Geoff Burke-USA TODAY Sports)
United States countrymen Frances Tiafoe and Brandon Nakashima showed off their tiebreaker prowess on Tuesday at the Mubadala Citi DC Open, winning their matches by taking back-to-back tiebreakers in Washington.

Tiafoe, the second seed, got past Russia's Aslan Karatsev 7-6 (5), 7-6 (5) in second-round action. Neither player broke serve in the match, with Tiafoe saving four brea