A fortuitous Diego Costa goal helped Spain overcome a dogged Iran to secure a 1-0 win in their World Cup Group B clash in Kazan.
Carlos Queiroz's side produced a defensive masterclass to reduce Spain to nothing more than half-chances during a hugely frustrating opening 53 minutes for the 2010 champions.
Costa - who scored twice in Friday's pulsating 3-3 draw with Portugal - eventually found the breakthrough, though, when Ramin Rezaeian's attempted clearance cannoned off his leg and into the bottom-left corner.
Iran had the ball in the back of the net just eight minutes later courtesy of Saeid Ezatolahi, but their wild celebrations were cut short after referee Andres Cunha was advised by VAR that Rezaeian's vital intervention had been made from an offside position.
Iran's approach was far more positive following Costa's strike, Mehdi Taremi heading just over from close range in what was their clearest opportunity to find an unlikely leveller.
The win moves Spain level on points with Portugal at the top of Group B and they know a draw against Morocco on Monday will be enough to secure qualification for the knockout stages. Iran, meanwhile, face Portugal on the same day needing a win to progress at the expense of Cristiano Ronaldo and Co.
Spain handed a 100th cap to Gerard Pique, with Dani Carvajal and Lucas Vazquez the only new faces from the side that drew against Portugal.
Any thoughts that Iran would be blown away by their more illustrious opponents soon dissipated as their expertly drilled defence comfortably rebuffed wave after wave of Spanish attack in the opening stages.
Fernando Hierro's side had to wait until the 25th minute for their first attempt on goal, David Silva's long-range free-kick comfortably held by Alireza Beiranvand.
The Manchester City midfielder came closer to breaking the deadlock five minutes later, but his hooked volley sailed narrowly over the crossbar from six yards out.
Spain's frustration was in danger of boiling over shortly before the interval when Costa got involved in an unnecessary spat with Beiranvand, although referee Cunha opted not to punish the combative striker.
Iran's resistance was nearly broken twice in quick succession at the start of the second period.
First, Pique's close-range effort was blocked and then Beiranvand palmed away Sergio Busquets' curled effort from the edge of the penalty area.
The Asian side almost scored the most unlikely of openers when Karim Ansarifard's instinctive effort from a corner flashed into David De Gea's side netting.
That near-miss was brought into sharp focus less than 60 seconds later when Costa picked up Andres Iniesta's pass inside the area and saw Rezaeian's attempted clearance ricochet off his leg and past the helpless Beiranvand.
Ezatolahi thought he had pulled Iran level shortly after the hour but his close-range finish after a scramble was ruled out courtesy of VAR after Rezaeian had strayed into an offside position.
Taremi's back-post header fizzed over De Gea's crossbar seven minutes from time as Iran pushed for an equaliser, but Spain held on for a 1-0 win they certainly deserved.
Key Opta Stats:
- Iran are winless against European opposition at the World Cup, having lost six of their seven fixtures (W0 D1 L6).
- There have been no 0-0 draws in any of the 20 games at the 2018 World Cup so far - the last time that this happened was in 1954 (no 0-0 scorelines in the 26-game tournament).
- Spain have won each of their last five World Cup matches when they have been drawing 0-0 at half time, all by a 1-0 scoreline.
- This result means all three matches on Wednesday ended 1-0. The only other days in World Cup history to see three 1-0 wins in a single day were June 25th 1982 and June 23rd 2010.
|This isn´t my last hurrah in Ryder Cup, insists Poulter|
|Barba back in NRL with North Queensland Cowboys|
|Arsenal wait on Mkhitaryan and Sokratis|
|All Blacks wary of Pumas pack ahead of Buenos Aires Test|
|Ryder Cup has special place in Pep Guardiola´s heart, says Fleetwood|
|Mbappe ready to take over from Messi and Ronaldo, says Trezeguet|
|Molinari: Ryder Cup pressure far outweighs any major|
|Koepka heads PGA Tour´s Player of the Year nominations|
|Lampard: Mourinho still a great manager|
|United States and Europe reveal Ryder Cup practice groupings|
|Bulldogs´ fine for ´Mad Monday´ antics halved|
|Bennett to leave Broncos after 2019 NRL campaign|
|American League postseason picture becomes clear|
|Steelers edge Buccaneers for first win|
|Gatland wants Webb available for World Cup|
|Modric: Ronaldo, Messi out of this world but my season deserved recognition|
|Love says Cavs ´will surprise a lot of people´|
|George believes Thunder can compete for championship this season|
|Messi is the greatest ever – Eto´o|
|Messi to miss Argentina´s upcoming friendlies|
|Dolphins say Hayes tore ACL attempting to avoid roughing-the-passer penalty|
|Modric deserved FIFA Best award – Ramos|
|Thibodeau open to potential Butler trade|
|Modric wanted Ronaldo, Messi at awards ceremony|
|Brewers´ Yelich active after elbow hit|
|Anthony on coming off Rockets´ bench: Whatever I have to do to help this team win|
|Raiders coach Gruden says Mack trade was hard on players|
|Bale lauds ´unbelievable´ Modric after FIFA Best triumph|
|Ronaldo, Messi lacked respect with FIFA Best awards snub - Capello|
|New Zealand the benchmark but England can win World Cup - Mitchell|
|FIFA Best Award a dream come true for Modric|
|Lakers a long way from Warriors, warns LeBron|
|Milner pokes fun at Salah´s Puskas Award win|
|Josh Rosen to replace Sam Bradford as Cardinals starting quarterback|
|Kaymer: Home-course advantage crucial to Europe hopes|
|Marta and Pedros win FIFA Best awards|
|I want to be in Toronto - Kawhi Leonard focused on Raptors, not future|
|Messi and Ronaldo lead FIFPro World XI as Salah and Neymar miss out|
|Knicks´ Kristaps Porzingis ´itchy´ to return but won´t commit to 2018-19 season|
|Modric beats Ronaldo and Salah to FIFA Best prize|
|49ers confirm ACL tear for QB Garoppolo|
|Salah beats Bale and Ronaldo to Puskas Award|
|Deschamps wins FIFA Best Men´s Coach award|
|Law to leave Windies for Middlesex role|
|Sunderland terminate Ndong´s contract|
|Spalletti warns rejuvenated Inter against complacency|
|Ryder Cup 2018: Figo in town as USA arrive in style|
|Browns name Baker Mayfield starting QB|
|Chelsea need to be more versatile, warns Giroud|
|Paris Saint-Germain FFP case referred by UEFA back to CFCB Investigatory Chamber|
|Busy Bertens ready for bed, Muguruza gains Wimbledon revenge|
|Hart ready if England come calling - Dyche|
|Ryder Cup 2018: An honour and a burden - the unique challenge of captaincy|
|Hibino beats Bouchard again at the Tashkent Open|
|Falcons lose Ricardo Allen for season|
|Mbappe three-match ban stands following appeal|
|Tomic wins first Tour-level match since Wimbledon in Chengdu|
|Ryder Cup diary: Scoreboard shocker, captains tight-lipped|
|Mourinho will spawn lots of managers - Lampard|
|Furyk outlines Woods´ Ryder Cup motivation|
|Tiger doesn´t scare Team Europe - Bjorn|
|Ryder Cup 2018: Team USA profile|
|Woods winning ´incredibly special for golf´, says Poulter|
|Grealish commits to Aston Villa with five-year deal|
|Ryder Cup 2018: Four reasons why Team USA will win|
|Herrera ready for return - Mourinho|
|Bellew determined to prove doubters wrong against Usyk|
|Lewandowski and Boateng´s professionalism impresses Kovac|
|WATCH: Sheepish Murray comically drops commemorative plate in China|
|Cech: Arsenal have forgotten how to win Premier League titles|