Grealish was pictured this summer lying motionless whilst on holiday and photographed inhaling nitrous oxide.
Having featured impressively for Villa towards the end of the season, many Villa fans felt let down by their young star, but new defender Richards has defended him.
Regarding the 19-year-old attacking midfielder, Richards said: "It's hard for youngsters coming through.
"I think he's a very talented boy but when you are going from earning – I don´t know what it is now – 80 quid a week at [the age of] 17 and then you sign for big money, I don´t know what he´s on, but thousands of pounds, it's like, you think you're the man. Don't you."
Richards came through the youth ranks at Manchester City and believes that Grealish will learn from his mistakes and develop as a footballer and as a person.
Richards continued: "As long as everyone learns from them, that's the key. We are only human, and you've got to enjoy life as well, but as long as you give it 100 percent when you are on that field, I think the rest takes care of itself."
Grealish will learn from mistakes - Aston Villa defender Richards
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