Top seed David Nalbandian marched into the Stockholm Open quarter-finals with a 6-3, 6-2 victory over Swede Joachim Johansson on Thursday.

Former world top-10 player Johansson, just back from retirement, struggled to cope with the steady baseline play of his Argentine opponent.

"I played good even though maybe I didn't return as well in the first set as I did in the second," said Nalbandian who next plays Spaniard Albert Montanes.

"I feel great indoors and I feel strong again. There were so many injuries in the beginning of the year," the world number seven told reporters.

Nalbandian capitalised on his first break point to open a 5-3 lead in the opening set.

He then broke to love to capture a 4-2 advantage in the second before going on to break serve again.

Earlier, Kei Nishikori scraped past Slovak Dominik Hrbaty 6-1, 1-6, 7-5 to clinch a meeting with second seed Mario Ancic of Croatia who put out Belgian Steve Darcis 7-6, 6-4.

Hrbaty, leading 5-4 in the third set, came within two points of victory before the Japanese player reeled off the last three games.

"This is the first time I've won so consistently and it surprises me," said Nishikori who has risen to a career-high 77th in the world after starting the year 288th.

"I haven't faced anyone from the top 10 (here) but it gives me confidence. Now I hope to go through to the semis."

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