Top Washington Nationals prospect Stephen Strasburg has pitched five innings in his minor league debut, throwing consistently in the 97-98 mph range while allowing four hits and four runs - one earned - with eight strikeouts and two walks for Harrisburg of the Double-A Eastern League.Strasburg also delivered an RBI double Sunday against Pittsburgh Pirates affiliate Altoona for his first professional hit.Strasburg threw 82 pitches and left with Harrisburg leading 5-4.