Three tournaments running, the Mexican league's Balón de Oro went to the Chilean running Toluca's midfield: Invierno 1997, Verano 1998, Verano 1999. Estay won the Mexican championship with Toluca in Verano 1998 and Verano 1999, played four matches at the 1998 World Cup as Chile reached the last sixteen, and finished with 69 caps and five goals between 1990 and 2001. Career record: 69 caps and 5 goals for Chile; club career at Toluca, Club América, Atlante.
| 1987–1991 | Club Deportivo Universidad Católica |
| 1991–1993 | FC St. Gallen |
| 1993–1995 | Olympiacos |
| 1993–1993 | Club Universidad de Chile |
| 1995–1995 | Club Social y Deportivo Colo Colo |
| 1996–1999 | Toluca |
| 1999–2001 | Club América |
| 2001–2003 | Atlante |
| 2003–2003 | Santos Laguna |
| 2004–2005 | Toluca |
| 2004–2004 | Club Deportivo Marte |
| 2005–2005 | América de Cali |
| Chile | 69 caps, 5 goals |
Chile legends whose careers overlapped Estay's
One rank above: Enrique Hormazábal at #23.
One rank below: Jaime Pizarro at #25.
Chile's editorial top five: Elías Figueroa · Alexis Sánchez · Iván Zamorano · Arturo Vidal · Claudio Bravo.