By Ashley Marshall, USTA.com
Team USA remained firmly in the medal hunt on Day 6 in Rio, one day after rain washed out the entire schedule of play.
Madison Keys guaranteed herself a spot in the medal round in women's singles, Steve Johnson booked his place in the men's singles quarterfinals and the mixed doubles duos of Venus Williams and Rajeev Ram and Bethanie Mattek-Sands and Jack Sock opened their campaigns with victories.
Keys got the U.S. top the perfect start on Thursday afternoon, romping past Russia’s Daria Kasatkina, 6-3, 6-1, in a ruthlessly efficient display that lasted just 53 minutes. Keys hit 30 winners to 19 unforced errors and faced just three break points while converting five of the nine she created on the Kasatkina serve.
The 21-year-old American, ranked ninth in the world, will now face either No. 2 seed Angelique Kerber in the semifinals. Keys is certain to play for a medal this weekend – if she beats Kerber, she will leave Rio with at least a silver medal. Should she lose that semifinal, she would play for a bronze medal against the loser of the Petra Kvitova-Monica Puig semi.
In the men's event, Johnson dropped just two games in his 64-minute thrashing of Russian Evgeny Donskoy. The 12th-seeded American broke serve six times in seven Donskoy service games to move into the quarterfinals, where he will play No. 2 seed Andy Murray of Great Britain, who rallied from 3-0 down in the final set to beat Fabio Fognini of Italy on Thursday.
Murray won their only previous meeting – a 6-2, 6-4 victory in the Shanghai Masters last year – but Johnson will take confidence from his latest win, especially how well he returned.
The 26-year-old California native broke in the fourth and sixth games of the first set as he reeled off five straight games to race out to an early advantage. The top-ranked American man in the draw kept that momentum in the early stages of the second set, opening up a 3-0 lead and breaking Donskoy all four times to seal the victory.
Team USA also had success Thursday in mixed doubles, which started 24 hours behind schedule after rain washed out all of the matches featuring Americans on Wednesday.
The first-time pairing of Venus and Ram rallied from a set down to defeat Kiki Bertens and Jean-Julien Rojer of the Netherlands, 6-7(4), 7-6(3), [10-8], in a third-set match super tiebreak. Their reward is a quarterfinal tilt with Roberta Vinci and Fognini of Italy, who upset No. 2 seeds Kristina Mladenovic and Pierre-Hugue Herbert of France in their first-round match.
Venus is competing in her fifth consecutive Olympics and is looking to win her fifth gold medal – her first in mixed doubles – which would set an Olympics tennis record.
The U.S.'s other mixed tandem, Mattek-Sands and Sock, had an easier time advancing to the quarterfinals, posting a routine 6-4, 6-3 victory over the British pairing of Johanna Konta and Jamie Murray. The Americans next face the home-country favorites, Brazil's Teliana Pereira and Marcelo Melo, who upset top seeds Nicolas Mahut and Carolina Garcia of France on Thursday.
Elsewhere on Day 6, Sock and Johnson fell to No. 5 seeds Florin Mergea and Horia Tecau, 6-3, 7-5, in the semifinals of the men's doubles but are still in contention for a medal. They will now face Daniel Nestor and Vasek Pospisil of Canada in the bronze medal match.
Overall, the U.S. will look to win its fourth men's doubles medal in the past eight Olympics, joining Ken Flach and Robert Seguso, who took gold in 1988, and Bob and Mike Bryan who claimed the top spot on the podium in 2012 and the bronze in 2008.
The United States has won 13 Olympic gold medals in men's and women's tennis, more than any other nation since tennis was reinstated as an Olympic sport in 1988. The next-closest nations all have two: Russia, Germany/West Germany, Switzerland and Chile.