The 21-year-old beat Belgian world No.94 Xavier Malisse in straight sets to continue his summer of success.

Lindahl dominated Malisse 6-1 in the first set but fell behind 5-1 in the second before launching a gutsy revival. He survived six break points to take the set to a tie-breaker, which he won 7-2 to end Malisse's comeback from an overturned drugs charge.

The Novocastrian's service game set up the victory. He won 76 per cent of his first-serve points, including eight aces.

Lindahl's coach, Shannon Bluhm, said yesterday's victory rated as one of his protege's best ever as he continued his build-up to his wildcard entry at the Australian Open.

"Malisse is a former top-20 player and is on the comeback, but he's still a top-100 player," Bluhm said.

"He [Lindahl] is definitely going to be dangerous for a top-100 player come the Australian Open."

Berdych is certain to be a harder assignment for Lindahl at Pat Rafter Arena today. The 196-centimetre Czech was ranked ninth in the world three years ago, but Bluhm said Lindahl could continue his giant-killing run.

"Berdych is a big server and a really tall guy, so if Nick can get out there and return well he could neutralise that advantage," Bluhm said.

The former Australian Open junior runner-up was rewarded for his strong summer form yesterday with a wildcard entry to this Saturday's Sydney International.

Davis Cup coach and national selector Todd Woodbridge said Lindahl might have turned a corner in his young career.

"By winning the wildcard play-off, we've seen Nick show a new maturity in his game and a real turnaround in attitude," Woodbridge said.