BRIDGETOWN, Barbados: Pakistan stumbled, following Mohammad Hafeez's second career hundred, and his century second-wicket stand with Asad Shafiq in the fourth one-day International against West Indies here on Monday.Pakistan hold an unassailable 3-0 lead in the best of five series and are bidding for their ninth successive victory in one day matches between the two sides.Hafeez struck seven fours and three sixes in the top score of 121 from 138 deliveries to lead the Pakistanis to 248 for nine from their allocation of 50 overs, after they were sent into bat on a hard, true Kensington Oval pitch under overcast skies.The Pakistan opener reached his milestone from 128 balls with a flick through mid-wicket for a single off Ravi Rampaul in the 42nd over.Hafeez added 153 for the second wicket with Shafiq, whose 71 from 102 balls contained four boundaries, before leg-spinner Devendra Bishoo continued to bowl impressively, taking three for 37 from his allotment of 10 overs to trigger a batting collapse.The visitors lost their way in the last 10 overs, losing seven wickets for 66 runs, to slide from a comfortable 182 for two, with Dwayne Bravo taking two for 60 from his 10 overs, Kemar Roach two for 67 from 10 overs, and two run outs helping to undermine them.Ahmed Shehzad was brilliantly caught by the elder Bravo running back from mid-wicket off Roach for six in the fifth over to set the Pakistanis back early.Hafeez and Shafiq then gave backbone to the Pakistan innings before West Indies fought back with some late wickets.Shafiq was caught at long-on off Bravo in the 39th over, and Pakistan captain Shahid Afridi was caught at mid-off off Roach for eight in the 41st over before the visitors reached the 200-run mark.Misbah-ul-Haq was bowled by Bishoo for five in the 44th over, as Pakistan added 45 runs in the Batting Power Play between the 41st and 45th overs. But three more wickets fell for one run in the space of seven deliveries. Hafeez was bowled in the 46th over by Bishoo, who had Hammaz Azam caught at fine leg before Mohammad Salman became the first of the two run-out victims.The Pakistanis were 220 for seven, and some lusty hitting from Tanvir Ahmed stretched their total towards the end.Both sides made two changes - West Indies brought Ramnaresh Sarwan and wicketkeeper-batsman Carlton Baugh Jr in to replace Devon Smith and fast bowler Andre Russell, while Pakistan Usman Salahuddin and Tanvir Ahmed came in to replace Umar Akmal and Wahab Riaz.The final ODI will be played on Thursday at the Guyana National Stadium.