Lukas Rosol, Martin Klizan and Mirza Basic made it through to the second round on the first day of the inaugural Sofia Open.

Rosol had to come from a set down to see off Robin Haase 3-6 6-3 6-4 in the opening match of the new indoor hard-court tournament on Monday.

The Czech saved five set points in the opener at the Arena Armeec Sofia before Haase finally took the opener.

Rosol recovered from losing his serve in the first game of the second set by winning four in a row and going on to level the match, then won his solitary break point of the decider to go through.

He told the ATP website: "It's always a battle. I got lucky at the end as Robin is playing good tennis. It's always about one or two points.

"After the Australian Open, which is outdoors, to then move indoors, is tricky. It's a different game and I'm happy with the result."

Seventh seed Klizan needed just shy of an hour to consign wildcard Alexander Lazov to a 6-3 6-0 defeat.

Klizan had a first-serve percentage of only 46, but was still able to ease into the second round by breaking the home hope six times.

Qualifier Basic ousted Yuki Bhambri with a 6-3 7-6 (7-4) triumph.