Colombo: Teenager Umar Akmal scored a brilliant maiden century and Rao Iftikhar's five wickets to power Pakistan Beat Sri Lanka by 146-runs in the fourth One-day international at Colombo on Friday.

Pakistan have beaten Sri Lanka by 146 runs in the fourth ODI of their five-match series in Colombo.

Umar Akmal's maiden international hundred, a rousing unbeaten 102 from 72 balls, and Younis Khan's first half-century as captain took Pakistan to a large total and set up their first win on tour.

Batting first has been distinctly advantageous at the Premadasa and so it proved as Pakistan put up a mammoth score and then pressured the Sri Lankan batsmen into self-destruction. Iftikhar Anjum played a major hand, claiming career-best figures as Sri Lanka were dismissed for 175, losing their last seven wickets for 45 runs in 12.3 overs.

Earlier, Umar's maiden international century and a dogged 89 from skipper Younis Khan lifted Pakistan to 321-5 after the tourists elected to bat in the day-night match at the Premadasa stadium.

Seamer Rao Iftikhar then grabbed 5-30 as Sri Lanka were shot out for 175 in 36.1 overs, handing Pakistan a badly-needed win after they were beaten 2-0 in the Test series and lost the first three One-dayers.

The fifth and final match will be played at the same venue on Sunday.

Umar, 19, younger brother of the team's wicket-keeper Kamran Akmal, pounded four sixes and five boundaries in only his third international.

Younis stayed rock-solid at the other end as Umar punished the wayward Sri Lankan attack during a fifth-wicket partnership of 176 runs after Pakistan slipped to 130-4.

Sri Lanka appeared to make light of the daunting target when they moved to 101-1 in the 16th over, before losing their last nine wickets for 74 runs.

Left-handed opener Upul Tharanga top-scored with 80 off 89 balls and skipper Kumar Sangakkara made 39, but none of the other top order batsmen delivered.

Spinners Shahid Afridi and Saeed Ajmal supported Iftikhar with two wickets each.

Earlier, Pakistan made a sound start as Imran Nazir, playing for the first time in the series, hit 23 in a first-wicket stand of 61 with Kamran Akmal by the 10th over.

Kamran then put on 45 for the second wicket with Younis to lift Pakistan to 106-1, before another middle-order collapse saw three wickets fall for 24 runs.

Leg-spinner Malinga Bandara, himself making his first appearance in the series, bowled Kamran and trapped Misbah-ul-Haq leg-before to finish with two for 44 in 10 overs.

Lasith Malinga went for 79 runs in his 10 wicketless overs, while fellow paceman Thilan Thushara took two wickets for 74 runs.

Sri Lanka rested three frontline bowlers, Muttiah Muralitharan, Nuwan Kulasekara and Dilhara Fernando, and replaced them with Ajantha Mendis, Bandara and Malinga.

Pakistan were forced to leave out the injured duo of Umar Gul and Abdul Razzaq and also dropped Nasir Jamshed and Fawad Alam.

They were replaced by Nazir, Mohammad Yousuf, Misbah and Iftikhar.

Brief Score: Pakistan 321 for 5 (Umar 102*, Younis 89, Kamran 57) beat Sri Lanka 175 (Tharanga 80, Anjum 5-31) by 146 runs.