Twice on 22 August 1993 he scored from midfield as Bolivia beat Venezuela 7-0 in La Paz, during the campaign that took the country to its first World Cup in 44 years. He played all three games at USA 1994, finished runner-up at the 1997 Copa América, and retired with 89 caps that stood as Bolivia's record until 2002, having won league titles with Blooming, Oriente Petrolero and The Strongest and played for both Boca Juniors and River Plate. Career record: 89 caps and 6 goals for Bolivia; club career at Club Blooming, Oriente Petrolero, The Strongest.
| 1979–1985 | Club Blooming |
| 1985–1988 | Boca Juniors |
| 1988–1989 | Club Atlético River Plate |
| 1989–1990 | Club Bolívar |
| 1990–1990 | Oriente Petrolero |
| 1991–1991 | Club Blooming |
| 1992–1992 | Everton de Viña del Mar |
| 1993–1993 | The Strongest |
| 1994–1995 | Cobreloa |
| 1995–1995 | Club Bolívar |
| 1996–1996 | Real Santa Cruz |
| 1997–1997 | Club Blooming |
| Bolivia | 89 caps, 6 goals |
Bolivia legends whose careers overlapped Melgar's
One rank above: Joaquín Botero at #8.
One rank below: Ramiro Blacut at #10.
Bolivia's editorial top five: Marco Etcheverry · Erwin Sánchez · Julio César Baldivieso · Víctor Agustín Ugarte · Marcelo Moreno Martins.