Debutant Fawad Alam scored an unbeaten century as Pakistan produced a remarkable turnaround to claw their way back in the second Test against Sri Lanka on Monday. The tourists, who were bowled out for 90 in their first innings, hit back to dismiss Sri Lanka for 240 and then cruised to 178-1 in their second knock by stumps on the second day. Left-handed Alam led the way with a determined 102 not out to give Pakistan a lead of 28 runs with nine wickets in hand on a dry pitch that appeared to have eased out under the hot sun. The fearless 23-year-old from Karachi moved to 98 by lofting left-arm spinner Rangana Herath for a six over mid-wicket and then flicked the next ball for two runs to reach the coveted century. Pakistan's fightback was launched by seamer Umar Gul and off-spinner Saeed Ajmal, who took four wickets each to keep Sri Lanka's first innings in check. The hosts lost their last seven wickets for 63 runs after starting the day at a comfortable 164-3.