P – Australian James Duckworth is out of the Citi Open in Washington, after being beaten by top seed John Isner in the second round.

The Australian struggled to handle the big-serving American, winning just nine points on return in the 6-3 6-4 loss.

Isner banged down 14 aces in the win, and dropped just three points on his first serve as he closed out the straight sets victory.

He could now face another Australian in the third round, with John Millman facing off against Cypriot Marcos Baghdatis to earn that right.

Fellow Australian and No.3 seed Bernard Tomic will also play on Wednesday (Thursday AEST), against Donald Young of the United States, after he received a first-round bye.

Isner joins fellow seeded players Steve Johnson, Ivo Karlovic, Gael Monfils, Alexander Zverev and Gilles Muller in the third round after they all enjoyed straight sets wins on the day.

Not so lucky was South African ninth seed Kevin Anderson, who fell 5-7 6-4 7-6 (7-3) to Tunisian Malek Jaziri in a a two and a half hour battle.

Also exiting the tournament was Serbian Viktor Troicki, who was humbled by American qualifier Ryan Harrison 7-6 (7-4) 6-4.

For world No.158 Harrison – who is still only 24 and was once considered a future star of American tennis – the win was sweet relief, especially as he only converted three of 22 break points.

“When you’re in a situation like I’m in – that you haven’t won a ton of matches – it seems like it’s tough to convert on opportunities. And it’s easy to get discouraged. You miss your first couple, and you feel like you’ve lost the match,” he said.

“For me, the biggest turning point for this week, compared to other weeks, has been when I’m not getting that first opportunity, (I’m) staying in there and creating more.”