The tournament hosts and South American side go head to head in Group A as they get the competition underway at the Al Bayt Stadium.
Felix Sanchez has lined up with a 3-4-3 formation spearheaded by the trio of captain Hassan Al-Haydos, Almoez Ali and Akram Afif, who have 104 goals between them on the international stage.
Abdulaziz Hatem and Karim Boudiaf, in possession of 222 caps between them, will feature in central midfield, while Bassam Al-Rawi, Boualem Khoukhi and Abdelkarim Hassan form the back three.
Meanwhile, Ecuador boss Gustavo Alfaro starts with Hernan Galindez between the sticks, despite fellow veteran goalkeeper Alexander Dominguez playing the majority of recent fixtures.
Brighton & Hove Albion pair Pervis Estupinan and Moises Caicedo feature at left-back and in midfield respectively, while the nation's record goalscorer Enner Valencia lines up in attack.
Midfielder Carlos Gruezo had been a fitness doubt and is only selected among the replacements.
Qatar: Al-Sheeb; Al-Rawi, Khoukhi, Haj Fadlalla; Ro-Ro, Boudiaf, Hatem, Ahmed; Al Haydos, Ali, Afif
Ecuador: Galindez; Preciado, Torres, Hincapie, Estupinan; Plata, Mendez, Caicedo, Ibarra; E.Valencia, Estrada
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