While on international duty with Chile, Sanchez recalled some of the horror problems faced by the players in the stadiums.
La Roja have had a miserable qualifying campaign so far for the World Cup - and the facilities are not up to scratch either.
After a disappointing 0-0 draw with Paraguay, Sanchez outlined the shocking conditions at the Juan Pinto Duran Sports Complex and Colo-Colo Stadium.
That included human faeces from his teammates coming out of the drain while they were in the dressing room.
"In Juan Pinto Duran there are three showers and they don't work," Sanchez said.
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"You have to wait for the other person to shower. At the Colo-Colo stadium I was sitting stretching and excrement from ourselves in the shower came out of the drain."
Chile had played at the Juan Pinto Duran Sports Complex on Friday evening when Sanchez had reported the nightmare conditions.
Both countries had a player sent off, with Victor Mendez and Paraguay's Robert Rojas both seeing red.
But it has left Chile fighting for a spot at the next World Cup after just one win in five qualifiers.
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They currently sit eighth out of 10 countries with the top four progressing to the tournament in Canada, Mexico and the USA in 2026.
Sanchez will be 36 at the time and would likely be his last major tournament with his nation if he has not retired by then.
The former Arsenal and Manchester United star is back with Inter Milan this season after one year at Marseille.