A listless Lleyton Hewitt came alive in the nick of time on Thursday to claim a place in the semi-finals of the U.S. Open with a 2-6, 6-1, 3-6, 6-3, 6-1 victory over unseeded Jarkko Nieminen of Finland.
The Australian will meet the winner of Thursday's other quarter-final between top seed Roger Federer and 11th-seeded Argentine David Nalbandian.
Hewitt, not showing his customary fist-pumping intensity, trailed the 57th-ranked Nieminen by two sets to one before he pushed his game into high gear.
The 2001 U.S. Open champion cracked 15 winners against only two unforced errors in the fifth set.
The defeat ended a rousing Open run by Nieminen, who became the first Finn to reach the quarter-finals of a Grand Slam tournament.
"It's nice to get through to another semi-final. Every match gets tougher," said third seed Hewitt, who will be making his fifth appearance in six years in the U.S. Open semi-finals.
"His game picked up, his serve picked up. I had to dig deep to find a way out of it."
Nieminen, the 1999 U.S. Open junior champion, beat Hewitt at his own game early on.
He pushed the Australian from side to side, changing pace and opening up angles to rip winners, especially off his piercing two-fisted backhand.
Hewitt looked lethargic when the left-handed Finn broke the Australian for a 5-3 lead in the third set with a backhand winner that brushed the line. Nieminen then held at love to seize the advantage.
The Australian earned the only break of the fourth set in the second game and when he held serve to force a fifth set, produced his first fist-pump of the match.
Hewitt's first trademark exhortation of "Come on!" came when he broke Nieminen, 24, in the first game of the fifth set with a curling forehand passing shot and the Australian was on his way to booking another appearance in the last four.
"Maybe I should have used them a bit earlier," he said about his shouts to encourage himself.