Jim Leyritz -- the guy who blasted one of the most famous home runs in Yankees World Series History -- says if he was running his ex-team ... he'd let A-Rod play as long as he wanted to.
A-Rod had said publicly that he wanted to play 3rd base during his final game Friday night -- but Yanks skipper Joe Girardi nixed the idea ... only allowing him to be a DH instead.
Some people are upset saying A-Rod deserved to go out on his own terms -- others say screw him, he's a cheater and doesn't deserve anything.
So, we put it up to Leyritz -- who played with Joe G. back in the day -- and he says in this situation, he disagrees with his old teammate.
"The guy's one of the greatest 5 players to ever play ... I would've played him until he wanted to stop."
Leyritz also says he thinks the decision may have been out of Joe's hands -- and even suggests Yanks brass took measures to ensure A-Rod wouldn't reach 700 home runs in pinstripes.