Vientos will remain behind in extended spring training to begin the season, Jonathan Mayo of MLB.com reports.
There's been no word of an injury for the Mets' No. 1 fantasy prospect, but after playing in 51 games at rookie ball last year as a 17-year-old, Vientos won't be rushed. He hit only four homers in 2017, but the power should come as he matures, marking him as a potential impact bat at third base.