World number one Rafael Nadal needed three sets to beat Bulgarian teenager Grigor Dimitrov 7-5, 3-6, 6-2 on Thursday and reach the quarter-finals of the World Indoor Tournament.
Nadal broke the 17-year-old Dimitrov in the first game but allowed him back on terms before he took the set after another break in the 11th game.
Dimitrov conquered the hearts of the 9,000 spectators as he won the second set but in the third Nadal proved too strong.
"He played very well today and has a lot of talent. He can be a top-10 player," Nadal told reporters after his second three-setter in Rotterdam in two days.
World number four Andy Murray recovered from a slow start to beat Italian baseliner Andreas Seppi 7-6, 7-5 in the second round.
"It was a difficult start, with too many mistakes and double faults but it improved in the second set," the Briton told reporters.
Second seed Murray, who cruised past Ivan Ljubicic in the opening round, varied his game more against Seppi in a match containing several long rallies.
"It was completely different from the first round but the long rallies on a fast court like this gave me back my rhythm," said the Scot.
Murray next meets 'lucky loser' Marc Gicquel, who came into the tournament after the withdrawal of Robin Soderling.
Gicquel reached the last eight by defeating fellow-Frenchman Paul-Henri Mathieu 6-4, 6-3.
Croatian Mario Ancic avenged his third-round defeat at the Australian Open by eliminating fourth-seeded Frenchman Gilles Simon 6-4, 3-6, 6-3, setting up a quarter-final with 2007 winner Mikhail Youzhny of Russia.
Michael Llodra, the 2008 champion, was beaten 6-4, 6-4 by fellow-Frenchman Gael Monfils.