WILLIAM Porterfield's demand that Ireland win all three group matches to reach the Super 10 stage of the World Twenty20 has been instantly revised after a horror start to their eighth global event.

A two-wicket defeat to Oman continues Ireland's downward trend in the shortest format, and follows losses to Papua New Guinea and UAE in their recent series in Australia and Abu Dhabi. They were described as “one-offs”; they are now becoming a worrying habit.

When Ireland took three wickets in the space of nine balls to reduce Oman, chasing 155 for victory, to 90 for five with just six overs remaining there looked to be only one winner. But then the wheels came off as Porterfield chose to replace Andy McBrine, who had just taken two wickets, with Paul Stirling, his second spinner after George Dockrell was left of the starting XI

Stirling conceded 11 runs in the over, Tim Murtagh's recall proved a nightmare for the Middlesex paceman as he started the 17th over with a no-ball, bowled two wides and the three extra balls were all crashed to boundary.

At the start of the last over, Oman's target was still 14 but again Porterfield ignored his best bowler, McBrine, and handed the ball to Max Sorensen's whose previous delivery had been hit for six.

A horrible chest high yorker was pulled to the mid-wicket boundary, the next ball actually bowled Amir but because it was a ‘free hit' they ran a bye and although Sorensen got lucky and earned a caught behind decision against Amir three balls later, his first ball to the new batsman was another above waist-high delivery which went through Niall O'Brien's legs for the runs which sparked wild celebrations in the Oman camp – the most unlikely of victories on their World T20 debut.

One person who did not deserve to be on the losing side was Gary Wilson who produced a stunning piece of fielding to save five runs, throwing himself backwards on the mid-wicket boundary to haul the ball back into play and stop the six.

It should have been the difference between winning and losing the match because it left Oman still requiring 21 from 14 balls. Boyd Rankin, in his first World Cup match since he declared for England in 2012 – he also bowled only three overs - maintained the Ireland momentum with a superb 19th over when he took a wicket and conceded just four singles. But Sorensen could not cope with the pressure of bowling the last over.

Sorensen, chosen just as much for his power-hitting, was not required to bat because Ireland finished on 154 for five, although again no batsman could go on and play a major innings. Both Porterfield and Stirling were dismissed for 29 and Gary Wilson for the second successive game top scored with 38.

A three-ball cameo from McBrine ensured every batsman reached double figures and had a strike rate of over 100 but this time it was the bowlers who let them down at the death.

Bangladesh won the first game of the day, defending 153 against Netherlands and Ireland now know tomorrow's game against the Tigers is, literally, win or bust.

“I backed the seamers at the death but two big overs cost us,” said Porterfield afterwards. “Now we have to get it right on Friday, but that's more a mental thing.

“Last time two wins would have taken us through on run-rate and it can happen again unless Oman win their two remaining games. If they do that, they fully deserve to go through.”

Oman's man of the match Aamer Ali hailed the preparations.

"We've done a lot of hard work before coming to the World Cup, and finally it has paid off," he said.