Paris - Novak Djokovic reached his 30th Grand Slam semi-final at the French Open on Thursday to move two wins away from a first Roland Garros title and a career Grand Slam.
The world number one defeated Czech seventh seed Tomas Berdych 6-3, 7-5, 6-3, claiming a place in an eighth Roland Garros semi-final and sixth in succession.
But the 29-year-old Serb, who will face either Belgium's David Goffin or Dominic Thiem of Austria for a place in the final, came perilously close to being disqualified in the second game of the third set.
Frustrated at missing a break point, the Serb smashed his racquet into the ground before it flew into the backwall on Philippe Chatrier Court.
Had it hit the nearby line judge, Djokovic would have been disqualified.
Not surprisingly, he offered a speedy apology for his actions to chair umpire Eva Asderaki Moore.
"It's the quarter-final of a Grand Slam, always a difficult match to play tactically," said Djokovic, a three-time runner-up in Paris whose quarter-final was played out in a damp chill where temperatures slumped to 12 degrees.
"The conditions were difficult but they are the same for all the players."
Djokovic's win was his 24th in 26 meetings against Berdych and his 11th in a row.
He raced through the first set with breaks in the seventh and ninth games before stretching out to a 4-2 lead in the second.
Berdych broke for the first time to get to 3-4 but Djokovic restored his advantage in the 12th game for a two sets lead.
The two men exchanged breaks in the first two games of the third before Berdych became angry over the deteriorating wet conditions.
"It's a circus, just one big circus," he fumed at tournament referee Wayne McKewen who took the players off for a brief stoppage to allow the rain to pass.
On the resumption, Djokovic broke for 5-3 and took victory when Berdych dumped a service return into the net.
Djokovic was playing for the third day in succession after a washout on Monday and just two hours of action on Tuesday.
If he is to win an elusive French Open title, the top seed, who is also the Wimbledon, US and Australian Open champion, will have to play five days in six.
Friday's other semi-final will see second seed Andy Murray take on Swiss third seed and defending champion Stan Wawrinka.