The 27-year-old striker was signed by Manchester United from Guadalajara in 2010 and went onto win two Premier League titles at Old Trafford.
Hernandez now finds himself with German club Bayer Leverkusen after becoming surplus to requirements under Louis van Gaal but still holds a firm affection for the club and in particular, legendary massager Ferguson.
"I was extremely lucky to be the first [Mexican] player to move to one of the biggest clubs in the world," he said in an interview with 'Movistar' as reported by Marca.
"I had a great time there. I had an incredible start, full of opportunities, although those opportunities dwindled over time and things took a turn for the worse.
"I'm so grateful to Ferguson. I think he's the best there's ever been, especially his squad management skills.
"Every player had his place. A squad player could still play 15 games a season.
"He opened the door to Europe for me and I won two league titles there."