NEW DELHI: Leander Paes reached the semi-finals of the $ 50,000 Bangkok Challenger with a straight sets win over second seed Alex Calatrava of Spain 7-6 (1), 6-3. Calatrava, ranked 106, had beaten Mahesh Bhupathi in the second round of the Ho Chi Minh Challenger, last week.After a tentative start, the Indian number one grew in confidence and dominated the net to win in 74 minutes. He has already collected 33 points which should take his ranking into the 130s.Paes, who is the highest ranked player left in the draw, will meet Gerard Solves (France) for a place in the final. There are no seeds left and the other semifinals will be Gouichi Motomura (Japan) who beat Bhupathi and Australia's Peter Tramachhi who won the Ho Chi Minh Challenger doubles title with Bhupathi.