He ended this by reaching the semifinals of the 2010 French Open, losing to Rafael Nadal after coming from two sets down to defeat Novak Djokovic in the quarterfinals.

He reached his first ATP Tour quarterfinal in the Internationaler Raiffeisen Grand Prix, defeating Sargis Sargsian and Andrea Gaudenzi in straight sets, before losing to eventual champion Nicolás Lapentti.

However, he did better in the Croatia Open by reaching the semifinals, defeating Vincent Spadea, Agustín Calleri, and Victor Hănescu, before losing to eventual champion Carlos Moyá.

The start of 2003 was not a good one for the Austrian, as he lost three consecutive Tour-level main-draw matches, including his Australian Open debut.

In 2004, the Austrian reached his first third round of a Grand Slam at the Australian Open with victories over Tomas Behrend, and Galo Blanco, before losing to Sjeng Schalken.

He next reached the quarterfinals of the Hamburg Masters with victories over Nicolás Massú, Irakli Labadze, and Marat Safin, but lost to former world No.

In the Canada Masters, he reached the quarterfinals, losing to Nicolas Kiefer, with straight-set victories over Andre Agassi and Fernando González.

At the SAP Open, he lost in the semifinals to Cyril Saulnier, but earned his third victory over Andre Agassi en route.

He reached his second ATP tour final at the Hypo Group Tennis International, but lost to Nikolay Davydenko in three sets.

In 2006, he continued his bad run with a 1–8 record and a seven-match losing streak in the first three months, with his only win coming in the Sydney International over Juan Ignacio Chela.

He won his first ATP Tour title at the Romanian Open, defeating Filippo Volandri in straight sets in the final, with victories over Gilles Simon and Paul-Henri Mathieu.

He ended the year with a quarterfinal showing at the Vienna Open, losing to Andy Roddick, but earned his first win over Juan Carlos Ferrero.

He then suffered a left wrist injury in his first-round loss to Nikolay Davydenko in the Gerry Weber Open which caused him to miss two months of tennis, including Wimbledon.

It was not until the Hypo Group Tennis International that he recorded back-to-back wins by reaching the quarterfinals, losing to Igor Kunitsyn in three sets.

He carried his good performance through the French Open with a third-round exit to Frenchman Gaël Monfils, having led two sets to one.

He then returned to clay at the Austrian Open and reached his seventh final, but lost once again to Juan Martín del Potro.

Melzer made a good performance at the Beijing Olympics by reaching the final eight, losing to eventual gold medalist Rafael Nadal.

[4] In 2009, Melzer again made a poor first quarter of the year, only managing one back-to-back win in his first ten tournaments, and it was at the Australian Open, where he reached the third round, losing to Andy Murray.

He also reached the quarterfinals of the Pilot Pen Tennis with a victory over Victor Hănescu, but lost in the following round to Fernando Verdasco.

He ended 2009 on a high note by winning his second career title at the Bank Austria-TennisTrophy over Marin Čilić in straight sets, which included a victory over Radek Štěpánek in the quarterfinals.

[4] Melzer lost in the first round of the Australian Open at the start of the season, but then reached the semifinals in Zagreb, losing to defending/eventual champion Marin Čilić.

He beat Dudi Sela and Nicolas Mahut before he caused a significant upset by defeating ninth seed David Ferrer in straight sets, followed by a four-set win over Teymuraz Gabashvili (who had beaten Andy Roddick in the previous round), and by a five set triumph over Novak Djokovic, coming back from a two-set deficit for the first time in his career.

[5] However, at the same tournament, he achieved his greatest success by winning the doubles title with German partner Philipp Petzschner.

In the last week of October, he won his third career title, defending his 2009 victory at the Vienna Open against his compatriot Andreas Haider-Maurer in a thrilling final; coming back from a set and a break down at 4–5 down (Haider-Maurer serving at 15–0) and three points away from defeat, to put up a heroic comeback and clinch the three set epic victory.

[7] Melzer's final tournament of the year as a singles player was the Paris Masters, where he advanced to the quarterfinals, before losing to world No.

Seeded ninth, he finally won consecutive matches as he beat Robin Haase, and Nicolás Almagro, to reach the quarterfinals for the first time in this tournament.

He did make the final in Brisbane in doubles, partnering Philipp Petzschner, and he won the tournament in Memphis against Canadian Milos Raonic.

However, the Paris Masters was back to a first-round exit in singles against Grigor Dimitrov and a first-match defeat in doubles.

At the Rome Masters he defeated John Isner and Marin Čilić to reach the third round, where he lost to Andy Murray.

He played his final tournament on the ATP Tour at the Vienna Open, where he partnered Alexander Zverev and also lost in the first round.