A 4-3 defeat to Oman on Tuesday saw the reigning champions slip to second place in Group D, setting up a mouth-watering win-or-go-home clash with Japan, themselves an Asian powerhouse with nine successive appearances at the FIFA Beach Soccer World Cup.

Iran finished third at the World Cup in 2017, and are currently second in the world rankings, but with the tournament now in its knockout stage, the only certainty in Thursday's match is that one of the Continent's powerhouses will see their campaign come to an early end.

The 4-3 win over the reigning champions saw Oman top Group D, and announce their credentials as potential Asian champions, but it will count for nothing if they fail to repeat the dose against Bahrain in the last eight.

While understandably pleased with his side's success against Iran, the highly experienced Hilal said the instant elimination that will follow any slip up against Bahrain makes the coming match an even tougher challenge.

So'od's side progressed to the knockout stage by the barest of the margins, advancing by virtue of their head-to-head record after finish level with Thailand on three points, with Thailand's parting 2-0 win over Afghanistan proving crucial.

But the level of the Southeast Asian side's play has steadily, and notably, improved, with player Shafiq Riza Huzair labelling their performance in Monday's 6-5 defeat to Palestine, the team's best ever.

So'od agrees the showing against Palestine was a new high, but said he is hoping the Malaysian side will deliver an even better display in their cutthroat quarter-final against the Emiratis.

The 75th-ranked Malaysians have advanced to the knockout stage for the first time in history, and now stand just two wins away from an unlikely berth at the FIFA Beach Soccer World Cup in Paraguay this November.

But standing in their way is an Emirati outfit who were Asian runners-up in 2017, have five FIFA Beach Soccer World Cup appearances under their belt and currently sit 12th in the global rankings.

After missing the 2017 tournament altogether, Palestine's perfect record of three wins from as many matches in Thailand means they are now potentially two wins away from a history-making berth at the FIFA Beach Soccer World Cup.

Hashim is excited by that prospect, and believes his side has the ability to become the seventh Asian nation to appear in the global showpiece.

"I hope (World Cup qualification) happens for us in Palestine," he said.

The result means Japan are set for a showdown with defending champions Islamic Republic of Iran in Thursday's quarter-finals, while Bahrain will face unbeaten Group D winners Oman.

Ozu Moreira and Masanori Okuyama scored twice each, with Ozu joining teammate Shusei Yamuichi at the top of the tournament scoring charts with six goals in three matches.

The result means Talib Hilal's side will face Bahrain in Thursday's quarter-finals, while Iran are set for a blockbuster, win-or-go-home clash against FIFA Beach Soccer World Cup regulars Japan.

The tie had been locked at 2-2 deep into the final period, but late goals to Sami Al Bulushi and Yahya Al Arami scored crucial late goals to give Oman what proved an insurmountable lead