By Ben Church, Issy Ronald, Patrick Sung, Alasdair Howorth, Adrienne Vogt, Matt Meyer and Seán Federico O'Murchú, CNN
It’s becoming a bit of a trend in this tournament for matches to remain 0-0 at half-time.
Both sides have had opportunities to score. Wales’ Kieffer Moore had a wide open goal early on but could not direct his header past Iran’s goalkeeper Hossein Hosseini while Ali Gholizadeh’s effort for Iran found the net but was ruled out by VAR for offside. Several late efforts by both squads also came to naught and we head into the break like we started!
Ali Gholizadeh looks like he makes it 1-0 to Iran but it's ruled out for offside by the video assistant referee (VAR)!
Some of Iran's players sang the national anthem loudly before kick-off in their match against Wales, but most remained subdued, barely moving their lips.
In the stands, Iranian fans cried listening to the anthem while the Welsh fans applauded them on.
From CNN's Ben Church in Doha
This year’s World Cup was moved to the winter to combat the extreme heat in the Qatari summer, but it's far from cold as Iran kicks-off against Wales.
Temperatures are hovering around 30 degrees Celsius (86 degrees Farenheit) and the desert sun feels particularly strong today – standing directly in it quickly becomes uncomfortable.
The heat will certainly be a factor for the first match of the day – perhaps more so for Wales with its players less accustomed to such intensity.
Half the pitch at the Ahmad Bin Ali Stadium is covered with shade so at least some of the players will have some respite.
Kick-off between Wales and Iran in a match which both teams need to get something out of, so expect some goals as the three points will be key to both teams' aspirations to make it to the knockout stage.
Let's go!
All eyes will be on Iran's players for reasons more than soccer before this game to see whether they sing their national anthem after they did not sing it before their opening game against England.
Outside the stadium of that game, CNN witnessed a number of Iran supporters wearing protest t-shirts, with slogans such as "Free Iran" or "Rise with the women of Iran."
Iran is appearing at this World Cup under the shadow of domestic turmoil, with its game against Wales taking place a day after the United Nations High Commissioner for Human Rights Chief, Volker Turk, said that the country is in a "full-fledged human rights crisis" as authorities clamp down on anti-regime dissidents.
Some additional context:
Soccer, like everything else in Iran, has been affected by the widespread protests, chaos and violence convulsing the country and threatening the very nature of the regime that has been in power for more than 40 years.
In the buildup to the World Cup in Qatar, there were calls for Iran to be thrown out of the tournament. As the team prepared to play England in its opening World Cup match, all eyes were focused on its players for more than soccer.
The protests, referred to by experts as the most significant since the establishment of clerical rule following the 1979 Iranian Revolution, were sparked by the death of Mahsa Amini, a 22-year-old woman who died after being detained by Iran’s morality police allegedly for not abiding by the country’s conservative dress code.
What began as a clamor for women’s rights has morphed into a movement, still driven by women, demanding the end of a regime that "people no longer believe…is reformable," Abbas Milani, director of Iranian studies at Stanford University, told CNN’s Christiane Amanpour earlier this month. "They want a different social contract without the clergy claiming divine right."
For both teams, who are side-by-side in FIFA’s ranking list, this feels like a must-win game in order to qualify for the knock-out stages from Group B.
Gareth Bale’s equalizer stole a late draw against the US Men's National Team for Wales in its opening game, keeping his side’s qualification hopes alive in its first World Cup in 64 years.
Iran, on the other hand, is looking to bounce back after a disappointing 6-2 defeat to England in its opening match and requires at least a draw today to maintain any chance of reaching the knockout stages.
Wales
Manager: Rob Page
Goalkeepers: Wayne Hennessey, Danny Ward, Adam Davies
Defenders: Ben Davies, Ben Cabango, Tom Lockyer, Joe Rodon, Chris Mepham, Ethan Ampadu, Chris Gunter, Neco Williams, Connor Roberts
Midfielders: Sorba Thomas, Joe Allen, Matt Smith, Dylan Levitt, Harry Wilson, Joe Morrell, Jonny Williams, Aaron Ramsey, Rubin Colwill
Forwards: Gareth Bale, Kieffer Moore, Mark Harris, Brennan Johnson, Dan James
Starting XI: Hennessey, Davies, Mepham, Rodon, Williams, Ramsey, Roberts, Ampadu, Wilson, Bale, Moore
Iran
Manager: Carlos Queiroz
Goalkeepers: Alireza Beiranvand, Amir Abedzadeh, Hossein Hosseini, Payam Niazmand
Defenders: Majid Hosseini, Hossein Kananizadehgan, Shoja Khalilzadeh, Morteza Pouraliganji, Sadegh Moharrami, Ramin Rezaeian, Milad Mohammadi, Abolfazl Jalali
Midfielders: Ehsan Hajsafi, Saeed Ezatolahi, Rouzbeh Cheshmi, Ali Karimi, Saman Ghoddos, Ahmad Noorollahi, Vahid Amiri
Forwards: Alireza Jahanbakhsh, Ali Gholizadeh, Mehdi Taremi, Mahdi Torabi, Karim Ansarifard, Sardar Azmoun
Starting XI: Hosseini, Mohammadi, Pouraliganji, Hosseini, Rezaeian, Haji Safi, Ezatolahi, Gholizadeh, Noorollahi, Taremi, Azmoun
