La Tri booked their place as automatic qualifiers from the South American group despite falling to a 3-1 away defeat to Paraguay on Thursday night.
Robert Morales’ early strike and a Piero Hincapié own goal in first half stoppage time put the hosts in front at the break.
Newcastle United star Miguel Almirón tripled Paraguay’s advantage just after half-time before Jordy Caicedo netted a late consolation goal from the penalty spot.
Paraguay’s Blas Riveros was sent off with two minute to go.
Albion winger Sarmiento came on in the second half for la Tri, his first senior appearance since surgery on his hamstring in December. Seagulls midfielder Caicedo, meanwhile, was suspended.
Ecuador’s place at this year’s tournament was confirmed thanks to Peru’s 1-0 defeat to Uruguay, a result which meant the Peruvians could not catch the Ecuadorians or Uruguayans.
Third-placed Ecuador and Uruguay, in fourth, both have 25 points with one qualifier remaining. Peru sit four points behind in fifth.
La Tri and Uruguay join South American group leaders Brazil and second-placed Argentina in Qatar in November.
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