BASEL, Switzerland (AFP) - Croatian fourth seed Marin Cilic stayed in touch for a possible place in the year-end final as he began the Swiss Indoors here on Wednesday with a defeat of German Philipp Petzschner 6-4, 6-4.

The German, also a first-round loser last week in Vienna, has gone a month without a decent result dating back six weeks ago to Metz, when he reached the quarter-finals against Richard Gasquet.

Gasquet was also in action on Wednesday and qualified for the second round with victory over Argentine Horacio Zeballos 7-6 (7/3), 6-4.

Cilic, losing finalist at the weekend in Austria to home favourite Jurgen Melzer, needs a massive performance in the last three weeks of the regular ATP season if he is to make a run for the eight-man ATP World Tour Finals in London from November 22.

The Croatian remains provisional 12th in the sprint for the last two spots in the year-end field, needing to nudge in front of provisional eight-placed Spaniard Fernando Verdasco.

He must start with a title in Basel, no easy ask with Roger Federer on hand and aiming for his fourth straight at home.

Cilic will face his second-round challenge against either Swiss sixth seed Stanislas Wawrinka or weekend Lyon victor Ivan Ljubicic of Croatia.

Gasquet earned a narrow win over the 42nd-ranked Zeballos with nine aces, saving both break points against his serve.

The Frenchman finally won a match after losing five of his previous eight, with the victory snapping a two-match losing streak in the first round.