Two goals in the group stage of the 1986 World Cup, against Iraq on 4 June and the hosts at the Azteca three days later, carried Paraguay into the second round. He was South American Footballer of the Year in 1985, won the Copa América in 1979 with three goals in the tournament, took the Brazilian title with Fluminense in 1984, and scored the winner in the Cosmos' Soccer Bowl victory in 1980.
| 1977–1979 | Sportivo Luqueño |
| 1980–1983 | New York Cosmos |
| 1983–1988 | Fluminense |
| 1988–1989 | FC Barcelona |
| 1989–1990 | Puebla |
| 1990–1991 | Sportivo Luqueño |
| 1992–1992 | Club Olimpia |
| 1993–1994 | Sportivo Luqueño |
| 1995–1995 | Club Cerro Corá |
| 1995–1995 | Club Deportes La Serena |
| 1996–1998 | Sportivo Luqueño |
Paraguay legends whose careers overlapped Romero's
One rank above: José Saturnino Cardozo at #4.
One rank below: Ever Hugo Almeida at #6.
Paraguay's editorial top five: Arsenio Erico · José Luis Chilavert · Carlos Gamarra · José Saturnino Cardozo · Julio César Romero.