Brett Favre is going to bat for his former teammate ... telling TMZ Sports Sterling Sharpe belongs in the Hall of Fame -- saying the guy's got a similar resume as Gale Sayers!
"If a guy like Gale Sayers and some other ones are in the Hall of Fame with a short career, absolutely he deserves to be in," Favre says of Sharpe.
Of course, Sterling was an absolute BEAST in the NFL for 7 seasons ... piling up 8,134 receiving yards and 65 TDs on 595 catches -- but a neck injury prematurely ended his career.