Carlos Queiroz's men turned in a battling display in Saturday's Group F fixture, and looked set to earn a memorable goalless draw until Lionel Messi struck a stunning injury-time winner.
Iran also felt they should have been awarded a penalty after Pablo Zabaleta felled Ashkan Dejagah nine minutes into the second half.
However, the Asian side still have every chance of qualifying for the knockout stages for the first time in their history - a win over the already eliminated Bosnia-Herzegovina and a defeat for Nigeria against Argentina would leave Iran level on points with their African rivals.
With just a two-goal difference between the sides, it is not inconceivable that Iran will progress, and Ghoochannejhad revealed his team-mates were still hopeful despite the pain of Saturday's loss.
"Thanks again for the great support yesterday," he tweeted. "Of course it still hurts, but we'll never lose hope! Thanks again!"
Get the best features, fun and footballing frolics straight to your inbox every week.
Thank you for signing up to Four Four Two. You will receive a verification email shortly.
There was a problem. Please refresh the page and try again.