The rabbi has had beer poured over his head and has been threatened by angry Reds fans.
But when things are going well, he has been mobbed by supporters wanting autographs and photographs.
After United clinched the Premier title at Wigan, the rabbi, who is responsible for Higher Prestwich Congregation in north Manchester, was surrounded by happy fans who blocked his route and jumped on his car.
Rabbi Saunders, a Reds fan since the age of nine, says that other supporters quickly spotted a similarity to Glazer soon after the 80-year-old billionaire took over the club.
He said: “Despite the fact that he’s about 30 years older than me, I guess there is a bit of a resemblance. We both have glasses and beards, although his is a bit more ginger than mine.
“Most of the time the comments are good hearted or people want to have their picture taken with me. On one or two occasions I have experienced some very ugly behaviour ranging from very strong language to having a can of beer poured over me.
“I’m used to it now but sometimes I wish Mr Glazer would let me borrow one of his security guards.
“Bizarrely, it’s also happened when I’ve been at FC United games where you would think fans would be a little bit surprised to see Malcolm Glazer.”
The 49-year-old has five children with wife Myrella – Shoshana, 25, Zevi, 24, Yossi, 19, Yoni, 14, and eight-year-old Chaya – who have been surprised by the attention received by their father.
Although a lifelong United fan, Rabbi Saunder’s religious beliefs mean that he cannot make games on Saturday, the Jewish Sabbath, but instead attends of mid-week and Sunday fixtures.
Glazer, worth a reported £1bn, drew criticism from Reds fans who feared his takeover would lead to price hikes.
What do you think? Look at the photos in the picture gallery and make up your own mind.