Martin Sheen in Court -- For Tom Sizemore?

Despite the drug busts, the tears and the Whizzinator, actor Tom Sizemore still has one famous fan left -- Martin Sheen.

TMZ spotted Sheen in Los Angeles County Superior Court this morning, sitting next to Tom's brother Paul. Sizemore is scheduled to be sentenced for violating probation in a drug case. Prosecutors are seeking a 16-month state prison term for the former "Black Hawk Down" star.

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