Both sides go into their final group game hoping that it will not be their last appearance at Russia 2018. 

The difference is that a draw would be enough for Portugal to progress, while IR Iran need a win to secure qualification and break new ground in the process as they have never advanced past the group stage in their previous appearances.

Diego Costa’s fortuitous goal nine minutes into the second half was all that separated the sides at Kazan Arena and the loss leaves Ansarfiard and his teammates needing to win their final game against Portugal to secure a place in the Round of 16.

Iran have never progressed beyond the group stages in any of their previous four appearances at the FIFA World Cup, with the Carlos Queiroz-coached team also falling short in Brazil four years ago.

But, with Iran only one point behind the Portuguese in Group B after two rounds of matches, the versatile Olympiacos star is confident Team Melli can find a way past Cristiano Ronaldo and company in Kaliningrad next week.

After a late own goal earned them the three points against Morocco, Lady Luck deserted Team Melli on Wednesday as Ramin Rezaeian's clearance struck Costa's leg and ended at the back of the Iranian net to consign them to their first defeat in official matches since 2014.

IR Iran threatened on the counter and from set-pieces, but having watched Saeid Ezatolahi's equaliser ruled out for offside, they failed to create more opportunities or take the few they created.

Team Melli currently sit third in the Group B standings, just one point below Portugal and Spain who are on four points, setting up a decisive final group stage match up with the Portuguese on June 25 at the Mordovia Arena.

“We showed that we were ready to suffer and ready to compete,” Queiroz said.

“I felt we deserved a better result. There’s no doubt Spain play wonderful, stylish football but I thought we deserved more for the way we played.”

A lucky Diego Costa goal handed hopefuls Spain their first win of the World Cup although a resilient Iran came close to causing a major upset.

Costa, who scored twice in a 3-3 opening draw with Portugal in Sochi, courted controversy early in the Group B encounter when he stepped on the toes of Iran 'keeper Ali Beiranvand as he waited to kick the ball out.

His gesture went unpunished, and the Atletico Madrid striker required another stroke of luck on 54 minutes when his shot came off Ramin Rezaeian to beat Beiranvand after he had been sent through by Andres Iniesta.

The entire Iranian bench poured onto the pitch when Saeid Ezatolahi fired an equaliser for Team Melli just before the hour.

But the thousands of Iranian supporters that filled the stadium with the sound of vuvuzelas throughout were left disappointed when it was ruled out for offside.

Team Melli showed lots of grit and determination to overcome a talented Morocco side in their opening match of the 2018 FIFA World Cup campaign on Friday.

Having not been able to create many chances, IR Iran were made to wait until the dying seconds to grab a winner as Ehsan Hajsafi's cross from a free-kick was sent into the back of the net by Bouhaddouz's misdirected flying header.

Wasteful finishing looked to have consigned this compelling contest at the Saint Petersburg Stadium to a goalless draw but Bouhaddouz's mistake in injury-time means Iran emerge as the early challengers to Spain and Portugal in Group B.

When Bouhaddouz nodded in at the near post, IR Iran's substitutes could not resist rushing onto the field and when the final whistle blew moments later they were sprinting over again in delight.

Morocco should at least take heart from a blistering first half an hour, during which their zip and zest deemed them virtually unplayable. But Hakim Ziyach, Ayoub El Kaabi and Mehdi Benatia all failed to capitalise.