From the relative comfort of familiar surroundings, Al Ain now find themselves in the belly of the beast.
The Pro League champions, no doubt inspired by last month's opening victory in the Asian Champions League, on Wednesday night face arguably their stiffest examination in this season's Group D: Esteghlal.
And a teeming Azadi Stadium.
"It's pretty brutal," said Mick McDermott, the fitness coach at Al Nasr who, during 16 months with the Iranian national team, experienced firsthand the white-hot atmosphere of the country's grandest ground.
"I've been at the Azadi when it's full - 100,000 people - and it's so deafening you can't hear the players five metres from you. The fans are really hostile, an all-male crowd, and the atmosphere gets pretty aggressive. Especially when a UAE team is in town."
Geographical proximity ensures there is much a stake this evening, as does both clubs' posturing as favourites in a pool that includes Al Hilal, the Saudi Arabian side, and Qatar's Al Rayyan.
Successful domestic campaigns - Al Ain and Esteghlal each sit top of their national league - allow the Champions League to assume priority; strenuous circumstances, therefore, call for strong minds.
In Asamoah Gyan and Mirel Radoi, Al Ain have players of World Cup and European Championship experience, while many of the first team thrived at last summer's London Olympics.
There is Helal Saeed, too, the 35-year-old midfielder who was clocking up Asian air miles long before Omar Abdulrahman had kicked a ball at the club's youth academy.
Although missing through injury, Saeed will be a voice in the dressing room where his experience will be vital. He has a winner's medal gleaned from Al Ain's 2003 crusade - their only success on the continent.
A trip to Iran is crucial to aspirations of a repeat.
"Our team is besieged by hardships but we work on overcoming them," said Mohammed Obaid Hammad, the first-team supervisor, before referencing Al Ain's exertions across four competitions, the Tehran climate and Esteghlal's fervent following.
"However, the experience of our foreign and local international players will lead us to overcoming the hostile atmosphere."
Such were Al Ain's concerns about what awaits in Tehran that at the beginning of this month they sent a representative to the Iranian capital, where issues regarding the stadium, training and hotels were resolved.
Then on Saturday a delegation flew to Iran to ensure the team's seamless transition. The squad arrived on Monday night.
"We were to leave Tuesday morning but changed to Monday evening …" Hammad said. "It gives the players enough time before the match to get used to the climate."
It is not simply pre-match paranoia. The Azadi Stadium is situated 1,200 metres above sea level and playing at high altitude, in theory, affects visiting teams more as the match creeps towards its conclusion.
However, Nick Worth, the medical services director at Al Jazira, disagrees.
Last season, the Abu Dhabi club battled Esteghlal at the Azadi having been told to expect energy reserves to quickly run low. They even considered training with altitude masks.
"Luckily we didn't do any of that," Worth said. "You don't notice the altitude. It's not enough to count."
The brooding Azadi crowd, though, is another matter.
"It's an incredibly intimidating atmosphere," Worth said. "It's a massive stadium that's really imposing, although a footballer should always want to play in front of the biggest crowds and at the best stadiums.
"And while the Azadi isn't the most lavish ground, Iranian fans love their football. It's so important to them."
Worth's words echo sentiments made by Ricardo Oliveira, Jazira's Brazilian striker, before last season's tussle in Tehran.
"I love the awesome atmosphere in the stadiums in Iran, lively and packed," he said.
"You can't get more inspired playing in front of such passionate fans."
Jazira's certainly seemed roused by the racket, claiming a last-gasp 2-1 victory that provided UAE football with their only Champions League triumph on Iranian soil. That remarkable record portrays the challenge that welcomes Al Ain.
"The Champions League is massive for Esteghlal and Iranian teams in general," McDermott said.
"The geographical rivalry makes it a huge tie, and given their budget is a fraction of Al Ain's, it's a major scalp to beat them.
"Then there's that intimidation factor. You walk into the Azadi - it's old, all concrete - and to the changing rooms in the belly of the stadium and around the long, dark hallways to come out of the tunnel where the roar of fans hits you. Visiting teams know then that they're in for a game."
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