Nicholas Castellanos leads the Cincinnati Reds (82-79) into a matchup with Bryan Reynolds and the Pittsburgh Pirates (61-100) on Sunday at 3:05 PM ET at PNC Park. Castellanos is batting .308, the fifth-best batting average in the league, for the favored Reds (-160), while Reynolds ranks eighth in MLB play with a .303 batting average this season for the underdog Pirates (+140)…