Left-hander Andy Oliver has opted out of his contract with Rays Triple-A affiliate Durham and been granted his release, per the Tampa Bay Times.
The 27-year-old Oliver managed decent numbers at that level this season, but struggled mightily with his control, walking 24 in 28 innings.
He has walked 401 batters in 611 2/3 minor league innings, which has pretty much doomed his career at this point.