Jo-Wilfried Tsonga failed to deal with blustery conditions and rain delays at the Kooyong Classic as he lost his first match of the Australian Open warm-up tournament.

33424 - Jo-Wilfried Tsonga suffers shock defeat in Melbourne

After winning his first event of 2012 last week in Qatar, the Frenchman succumbed to Jurgen Melzer 6-4 6-2, failing to find his rhythm throughout the match. Melzer, the world No. 33, bowed out in the first round of the Brisbane International last week, but made amends on Wednesday as he looks to step up preparations for the first grand slam of the year.

Tsonga did provide some cause for concern for Melzer as the Austrian was broken while serving for the match at 5-2 in the second set. However, Melzer responded brilliantly to break back immediately, sealing the upset win over the world No. 6 with a delightful crosscourt backhand.

Australian teenager Bernard Tomic overcame a first-set hiccup to defeat Tomas Berdych 4-6 6-3 6-4. Tomic, a Wimbledon quarter-finalist, took time to adapt to the swirling conditions, but maintained control of the match over his more experienced opponent thereafter.

At the Sydney International there was a shock exit for second seed John Isner, who fell to fellow American Bobby Reynolds 3-6 6-4 6-3. Isner fired down 20 aces during the match, but managed to win a meagre 13 points on Reynold's delivery in the final two sets as he let a first-set lead slip.

There were no such troubles for Juan Martin Del Potro who cruised through his second round contest with Lukasz Kubot. The top seed bagged a 6-4 6-2 victory in 95 minutes to set up a quarter-final showdown with Marcos Baghdatis who edged Australia's Matthew Ebden 3-6 7-5 7-6(3).

Richard Gasquet also notched a comfortable win as he cruised past Fabio Fognini in 55 minutes.