Vientos was scratched from the lineup for Sunday's game against the Mariners due to left ankle soreness, Anthony DiComo of MLB.com reports.
The ankle issue has apparently been bothering Vientos since late July and cost him a start Aug. 5 against the Cardinals, but he had been part of the lineup in four of the Mets' subsequent five contests. Assuming Vientos isn't dealing with any sort of major setback with the ankle, he should have a good chance at returning to the lineup for Tuesday's series opener versus the Athletics following Monday's team off day.