Third-seeded Grigor Dimitrov of Bulgaria defeated Zhang Zhizhen of China 6-4, 7-5 in the men's singles first round at the Erste Bank Open in Vienna, Austria, on Wednesday.

In his first match against world No. 9 Grigor Dimitrov, world No. 46 Zhang broke the opponent in his first service game. The Bulgarian responded a break point in the sixth as the match remained close.

Zhang had the chance tie the battle 5-5 when he earned a game point in the 10th, but he conceded three straight points and lost the set.

Zhang continued to fight with remarkable resilience in the second set, matching Dimitrov in holding all of his first five service games. The 28-year-old Chinese had the chance to clinch Game 11 and lead when he forced a break point, but Dimitrov saved it with an excellent forehand. He came back to take two straight games and won the match.

"The conditions from last week to today are so different. In the end, I just had to somehow find a way, but I have so much experience in moments like that," Dimitrov told reporters. He lost to Tommy Paul of the U.S. in the Stockholm Open final last week.

"At the beginning, I was playing alright, but I wasn't able to hit my spots on the serve very well," the Bulgarian added. "In the second set, I almost had too many opportunities, but in the last game, I had a little more authority which helped me to step through and put a little more pressure on him."

Dimitrov will face Tomas Machac of the Czech Republic next at the tournament.