ISLAMABAD - The 50th Men's National Basketball Championship could not have a better start as Khyber-Pakhtunkhwa (KP) stunned Navy 71-69 in the tournament's opener here at the PSB on Thursday. The defeat means that Navy, one of the most consistent sides at the national circuit, might finish second in their three-team Group B and ultimately face a comparatively tougher team in the quarter-finals. There was very little chance to choose from both sides in the first two quarters as the fast-paced match saw both sides struggling to take clear advantage. Navy scored 14 and 21 points in the first two quarters while Khyber-Pakhtunkhwa added 12 and 22, just one point separated the teams. Navy boosted the tempo in the third quarter with some skilful play and availed opportunities and also defended stoutly. The sailors scored 16 points in the 20-minute period and restricted Khyber-Pakhtunkhwa to 11 and entered the final quarter with a healthy six-point lead. Khyber-Pakhtunkhwa needed to play out of their skin to register an upset and they did exactly that. The boys from KP showed a lot of intensity in the fourth quarter and wrested the initiative with a fine display of basketball -- they were brilliant in offence and also looked great in defence. Navy, on the other hand, seemed to have lost their touch a bit. They seemed under pressure and started making mistakes and Khyber-Pakhtunkhwa took full advantage and scored 26 points in the final quarter and restricted Navy to 18 to record a narrow two-point victory. Waqas was best player from Khyber-Pakhtunkhwa with a contribution of 18 points. Safeer Khan provided excellent assistance with 15 points. Navy's Ghulam Mustafa was easily the most impressive player of the match. The tall centre did most of his side's scoring and ended up with 32 points against his name. Ali Nawaz chipped in with 12 points. Pakistan Basketball Federation President Asif Bajwa was the chief guest at the opening ceremony. As many as 13 teams are taking part in the championship. PAF, HEC and HBL are played in Group A. Group B has Navy, Sindh and Khyber-Pakhtunkhwa. Pakistan Ordnance Factories, Wapda and Railways make up Group C while Fata, Balochistan, Islamabad and Punjab are bracketed in Group D. The top two teams from each group will qualify for the quarter-finals, which will be played on May 30. The semi-finals will be held on May 31 while the final is slated for June 1.