Nadal flexes his muscles

In another fourth round match, lower back pain, tennis shoes without traction and a feisty opponent were no match for Novak Djokovic. The fourth-seeded Serb reached the quarter finals for the first time, stumbling and tumbling on the grass court, before beating 2002 champion Lleyton Hewitt 7-6 (8), 7-6 (2), 4-6, 7-6 (5).

Djokovic fell to his knees after winning, then got up, took off his shirt and pounded his chest with his fist while looking at his parents, who were hugging and cheering in the players’ box.

Djokovic, who was twice treated during the match for a right lower back problem, received a boost on his serve on the first point of the fourth-set tie-breaker when he successfully challenged his forehand being called long.

Marcos Baghdatis reached the quarter finals for the second year running beating Russian grinder Nikolay Davydenko 7-6, 7-6, 6-3.

Venus Williams had a much easier time today, playing outstanding tennis to reach the semi-finals by beating No. 5 Svetlana Kuznetsova 6-3, 6-4. Williams will next face French Open finalist Ana Ivanovic, who defeated No. 14 Nicole Vaidisova 4-6, 6-2, 7-5.

Williams started the season with a wrist injury and is not even ranked in the top 30. Seeded only No. 23 at the All England Club, she struggled early in the tournament, needing three sets to beat 59th-ranked Alla Kudryavtseva in the first round and coming within two points of defeat against 71st-ranked Akiko Morigami in the third.

On Wednesday, she easily beat 2004 champion Maria Sharapova in a match that started Tuesday but was suspended for the night after only three points were played.

Ivanovic saved three match points and beginning with the last one, won 13 of 15 points. That sent her on her way to taking the match’s last four games. It ended when Vaidisova double-faulted for the sixth time.

“I knew I could do it,” Ivanovic said. “I knew I could make some good shots and be aggressive and move forward and put pressure.”

Nadal’s third-round match, which began on Saturday, didn’t finish until Wednesday. The three-time French Open champion failed to convert his first match point on Monday, and had to wait until Wednesday to get another because of rain delays.

Nadal is trying to become the first man to win the French Open and Wimbledon in the same year since Bjorn Borg in 1980.

In the quarter finals, the second-seeded Spaniard will face No. 7 Tomas Berdych, who beat Jonas Bjorkman 6-4, 6-0, 6-7 (6), 6-0.

No. 10 Marcos Baghdatis, who lost to Nadal in last year’s semi-finals, advanced by beating No. 6 Nikolay Davydenko 7-6 (5), 7-6 (5), 6-3 in the fourth round.

There was one brief rain delay on some courts today, meaning it has drizzled on nine of the tournament’s 10 days. But Wimbledon referee Andrew Jarrett was confident the tournament would finish on time.