henman hopes ended in dubai third seed tim henman slumped to a straight sets defeat in his rain-interrupted dubai open quarter-final against ivan ljubicic.  the croatian eighth seed booked his place in the last four with a 7-5 6-4 victory over the british number one. henman had looked on course to level the match after going 2-0 up in the second set  but his progress was halted as the rain intervened again. ljubicic hit back after the break to seal a fourth straight win over henman. earlier in the day  spanish fifth seed tommy robredo secured his semi-final place when he beat nicolas kiefer of germany 6-4 6-4. afterwards  henman was left cursing the weather and the umpire after seven breaks for rain during the match.  it was incredibly frustrating   henman said.  it s raining and the umpire doesn t take control.  he kept telling us to play till the end of the game. but if it s raining  you come off - the score s irrelevant.  it couldn t be more frustrating as i was very happy with my form until now. you don t expect this in the desert.