Forest moved onto the 50-point mark thanks to Blackstock's two goals which eventually saw off a sprited Portsmouth side.
Having posed a below-par home record throughout the campaign the Reds at least gave their supporters a good send-off to keep them going through the summer months.
For Pompey it's League One and an uncertain future, for Forest the consolation that until two months ago they looked set for a similar fate.
Match report and reaction to follow over the weekend on Forest Mad.