La Russa leaves on top, after leading the St. Louis Cardinals to its second World Series title during his tenure.
Tony La Russa managed in St. Louis for 16 of his 33 seasons as a skipper.
The 67-year old won the Cardinals two World Championships, three National League pennants and made the playoffs nine times.
Back in 1989, La Russa also won a World Championship while managing the Oakland A's.
La Russa told reporters Monday that he decided in mid-August that this would be his last season, he told only general manager John Mozeliak.
La Russa says he's done managing and doesn't want to be a GM.
"If you take all of those factors, there isn't one that dominates," said Tony La Russa. "They all just come together tell you that the time is over. But, I just went through the season and I felt that I think it feels like it's time to end it. And I think it's going to be great for the Cardinals to refresh what's going on here with the field manager job."
La Russa's parting words to Mozeliak find my replacement.
La Russa won three World Championships, and 2,728 games second behind Connie Mack and John McGraw, only 36 away from second place.
He along with Sparky Anderson the only managers to win titles in both leagues.
And he managed for 33 seasons with the Cards, A's and White Sox.
KOLR10 has also learned La Russa will make an appearance on The Late Show with David Letterman Monday night.
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