And, in a moment that made ever City fan smile, Grealish delivered his promise to young 11-year-old supporter Finlay with a special, dedicated goal celebration.
Finlay, like Jack’s sister, Holly, has cerebral palsy and he’s been hugely impressed by the way Jack involves her in everything he does.
Finlay sent a letter to express his gratitude and Jack returned the favour with a signed City shirt before surprising him at the CFA where he plays every Monday as part of the disability football team.
After striking up a friendship, Jack told Finlay he could select his next goal celebration, which he wonderfully performed after today’s goal.
Grealish joined Jude Bellingham, Bukayo Saka (2), Raheem Sterling and Marcus Rashford on the scoresheet in the comfortable Three Lions win.
Bellingham opened the scoring on 35 minutes as he headed home his first international goal from Luke Shaw's pinpoint cross.
Arsenal winger Saka doubled the advantage on 43 minutes by scoring a stunning volley following a headed ball into his path by Harry Maguire.
Former City man Sterling made it three in first half stoppage time when he prodded home after a cross into the danger zone by captain Harry Kane.
Saka made it four on 62 minutes as he jinked back and forth in the box before firing home.
Iran pulled one back just three minutes later with an impressive finish from Mehdi Taremi which left Pickford no chance.
Rashford made it 5-1 moments later when he slid home a left foot shot, less than a minute after coming on himself.
And Grealish completed the scoring for the Three Lions when he eased home in the box after a clever cutback from fellow substitute Callum Wilson.
Taremi bagged a consolation for Iran in stoppage time with a cool penalty past Pickford.
England's next game is this Friday as they face USA at Al Bayt Stadium, kick-off 19:00 (UK).