Ireland, chasing 338 for victory, were skittled out for just 82 inside 24 overs, with left-arm spinner Imad Wasim taking five wickets for 14 runs. This was the seventh largest victory, in terms of runs, in the history of one-day internationals.
Earlier, Pakistan piled up 337 for six in a match reduced by rain to 47 overs per side, with Sharjeel Khan’s 152 the third quickest 150 in the format in terms of balls faced.
Imad Wasim took five wickets for just 14 runs, while Umar Gul marked his return with three wickets for 23 runs, as the Irish team was left hapless against the Pakistan bowling.
Sharjeel Khan’s stunning innings of 152, his maiden one-day international hundred, guided Pakistan to a formidable 337 for six in their series opener against Ireland at Malahide on Thursday.
Sharjeel hit the third fastest 150 in ODI cricket from just 85 balls, with 16 fours and nine sixes to put the tourists in control at the halfway stage in a match reduced by rain to 47 overs per side.
Only South Africa’s AB de Villiers and Australia’s Shane Watson have reached the landmark quicker than the Pakistan opening batsman and although Sharjeel was out next ball, caught behind off Barry McCarthy, he had set his side up for a huge total.
What made the 27-year-old Sharjeel’s feat all the more impressive was that Thursday’s match was just his 12th ODI, with his previous highest score 61.
After he was out, the experienced Shoaib Malik and debutant Mohammed Nawaz then put on 105 for the sixth wicket in just 83 balls with only McCarthy standing up to the onslaught.
The Durham medium-pacer finished with his second four-wicket haul in only his seventh ODI, while wicket-keeper Niall O’Brien held four catches. But it was Sharjeel who stole the show in a memorable innings.
He passed his best ODI score, in his previous innings, with three successive fours off Peter Chase and brought up his hundred from just 61 balls with his 12th four to go with five sixes.
Pakistan lost a wicket in the fourth over when skipper Azhar Ali was caught behind to McCarthy’s ninth ball but Mohammad Hafeez helped the recovery in a second-wicket stand of 90, and Sharjeel and Babar Azam then put on 94 for the third wicket in just 63 deliveries.
The only time Pakistan were troubled was when Sarfraz Ahmed followed Sharjeel back to the pavilion just three balls later to leave Pakistan 227 for five.
But Malik and Nawaz, on a very impressive first appearance, continued to take apart Irish spinners Andy McBrine and Paul Stirling, who conceded 107 runs in their combined 12 overs.
Ireland made just one change to the team that won the last ODI against Afghanistan last month to tie the series at 2-2, with the experienced Niall O’Brien returning from injury to replace Sean Terry
Pakistan included two debutants in spin-bowling all-rounder Mohammad Nawaz and seamer Hasan Ali, in a side captained by Azhar Ali, their limited overs skipper.
There is also a return to ODI side for the first time in 16 months for the experienced Umar Gul. But paceman Wahab Riaz and leg-spinner Yasir Shah, who both featured in the recent 2-2 drawn Test series against England, were omitted.
This is the first of a two-match series, with the teams set to return to Malahide, near Dublin, on Saturday ahead of Pakistan’s five-match ODI campaign in England.
Azhar Ali c N O’Brien b McCarthy 1
Sharjeel Khan c N O’Brien b McCarthy 152
Mohammad Hafeez c Porterfield b Chase 37
Babar Azam c N O’Brien b McCarthy 29
Sarfraz Ahmed c N O’Brien b Murtagh 2
Shoaib Malik not out 57
Mohammad Nawaz c Stirling b McCarthy 53
Imad Wasim not out 0
Extras (lb3, w3) 6
Total (6 wkts, 47 overs) 337
Did not bat: Hasan Ali, Umar Gul, Mohammad Amir
Fall of wickets: 1-17 (Azhar Ali), 2-107 (Mohammad Hafeez), 3-203 (Babar Azam), 4-226 (Sharjeel Khan), 5-227 (Sarfraz Ahmed), 6-332 (Mohammad Nawaz)
Bowling: Murtagh 10-0-38-1; McCarthy 10-1-62-4; Chase 7-0-70-1 (1w); McBrine 5-0-49-0, K O’Brien 8-0-57-0; Stirling 7-0-58-0 (2w);
P. Stirling b Mohammad Amir 0
E. Joyce c Hasan Ali b Umar Gul 9
W. Porterfield b Umar Gul 13
N. O’Brien st Sarfraz Ahmed b Imad Wasim 10
K. O’Brien c Sarfraz Ahmed b Umar Gul 4
G. Wilson st Sarfraz Ahmed b Mohammad Nawaz 21
S. Poynter lbw b Imad Wasim 4
A. McBrine not out 14
B. McCarthy b Imad Wasim 1
T. Murtagh b Imad Wasim 0
P. Chase b Imad Wasim 0
Extras (lb2, w4) 6
Total (all out, 23.4 overs) 82
Fall of wickets: 1-0 (Stirling), 2-22 (Porterfield) 3-28 (Joyce), 4-32 (K O’Brien), 5-51 (N O’Brien), 6-55 (Poynter), 7-81 (Wilson), 8-82 (McCarthy), 9-82 (Murtagh), 10-82 (Chase)
Bowling: Amir 4-1-7-1 (1w); Malik 1-0-1-0; Gul 5-0-23-3 (2w); Hasan 5-0-21-0 (1w); Imad 5.4-0-14-5; Nawaz 3-0-14-1;
Result: Pakistan won by 255 runs
Series: Pakistan lead two-match series 1-0
Remaining Fixture: Aug 20: 2nd ODI, Malahide