Washington, DC, USA, 6 August 2015 | tennis.com.au

Aussie Sam Groth has continued his stellar recent form to upset top 20 star Viktor Troicki at the ATP/WTA Citi Open in Washington DC.

Groth dominated the No.9 seed in just 69 minutes, winning 6-3 6-4 to advance to the third round.

Groth’s compatriot Lleyton Hewitt came close to joining him, yet fell in a thriller to seventh seed Feliciano Lopez.

The Australian veteran started strongly yet the Spaniard outlasted him to win 4-6 7-5 6-3.

Lopez next faces Groth.

Later on Wednesday, Bernard Tomic fell in three sets to American Steve Johnson in the second round.

Tomic, the tournament’s 11th seed, got off to a good start but watched as Johnson roared back into contention; the world No.55 eventually ran out the match a 6-7(7) 6-4 6-2 winner in two hours.

Groth and women’s No.2 seed Sam Stosur are the remaining Aussies at the Citi Open.