Sanchez scored 30 goals in all competitions last season but could not help secure a top four spot for the Gunners.
Slovenian referee Damir Skomina initially awarded it but then, more than minute later, he suddenly reversed the decision on the advice of the VAR, Clement Turpin of France. Defeat in an extreme meeting in a friendly match against Romania, I will directly say it was a big surprise, despite the fact that the Romanians scored as many as three goals scored.
Sanchez charged through the Chilean defense, but saw his shot saved by Ondoa, only for Vargas to score the rebound.
Chileans from the first seconds pressed Cameroon to their goal - Vargas in the first minute shook the rod, and with a kick Fuensalida coped, Ondoa.
However, clear chances were hard to come by until Vargas fired high and well over the bar after being played into a pocket of space in the 40th minute by Vidal. The pace has now been set for the African champions, the indomitable lions of Cameroon who are expected to enter the saga tomorrow against The south American champions, la Roja of Chile.
In the second period Cameroon were resigned to very few notable efforts with captain Benjamin Moukandjo firing his free-kick wide.