By Tom Victor Some 20 years on from Manchester United’s infamous defeat at Porto in the Champions League, one key figure is part of the furniture at Old Trafford. It’s not Ryan Giggs or Paul Scholes, the long-serving stars who remained on the playing staff for the best part of 20 years between them after the painful reverse. Nor is it Jose Mourinho, the Porto manager that year and United’s boss 12 years later, with the Portuguese getting his marching orders in December 2018. Instead, it’s the man who scored both goals in Porto’s first-leg win at the end of February 2004, giving them an advanta…