London, England, 4 July 2013 | AAP

Australian world No.1 junior Nick Kyrgios has suffered a heavy defeat in the third round of the boys singles at Wimbledon.

Top seed Kyrgios was thumped 6-2 6-2 by Korean Hyeon Chung in a surprise result on Wednesday.

Australia’s involvement in the juniors ended with Thanasi Kokkinakis, who lost to Kyrgios in the junior Australian Open final, also defeated on Wednesday.

He fell to Serbian fourth seed Laslo Djere 3-6 6-2 6-0.

Kyrgios, 18, impressed on his Grand Slam main draw debut at the French Open last month, beating Czech veteran Radek Stepanek in straight sets.

Aussie junior results Day 9

BOYS’ SINGLES

Hyeon Chung (KOR) d Nick Kyrgios (AUS) [1] 6-2 6-2

Laslo Djere (SRB) [4] d Thanasi Kokkinakis (AUS) 3-6 6-2 6-0

BOYS’ DOUBLES

Jay Andrijic (AUS)/Bradley Mousley (AUS) d Evan Hoyt (GBR)/Wayne Montgomery (RSA) 6-3 7-6(4)