Israel's Shahar Peer continued her remarkable run at the $2m Dubai Championships with a quarter-final victory over Li Na.AFP adds:
Peer was leading 7-5 3-0 against the world number 10 before the Chinese player retired with a lower-back injury.
Peer is the first Israeli to compete in the United Arab Emirates and has caused a huge security concern for officials following the recent Dubai assassination.
The world number 22 has played each of her four games on the outside courts, which provide easier coverage for security officials, and her semi-final clash is also likely to be played away from the 5,000 seat main arena.
"We have to take it day by day," said tournament referee Alan Mills. "The tournament has said that security is paramount. And it is the security and police who dictate what happens.
"So we will have to wait and see. We have already said - if she gets to the final, where are 5,000 people going to sit? It's something that they have obviously got in hand."
Peer will play the winner of the quarter-final between defending champion Venus Williams and Anastasia Pavlyuchenkova.
Peer extended her career-best sequence to a victory over Li Na, the world number ten from China, who retired while trailing 5-7, 0-3, increasing the possibility that the Israeli will now be scheduled on to the centre court for the first time.
That might afford less protection for Peer than the secluded, tree-lined, limited access outside court on which she has so far played.
And with the political fall-out from last month's Dubai assassination, and the finger being pointed at Israeli agents, the temptation will be not to take this risk.
At the same time, with Venus Williams a favourite to win her quarter-final against Anastasia Pavlyuchenkova in the same half, there will be pressure for new plans to be considered.
About 5,000 people have bought centre court tickets for semi-finals day expecting to see one of the world's leading players - and Williams, the five times former Wimbledon champion, is the only big name left in the tournament.