In general, interleague games tend to go under just due to the fact of the unfamiliarity of the teams and pitchers. Civale takes the hill for the Indians, and he is off to an impressive start to his young career. He has a 1.50 ERA in 4 starts, but what is more impressive is the fact he has held elite offenses like the Yankees to just 2 earned runs, Twins 1 earned run, and Rangers 1 earned run.
Syndergaard has posted a 1.65 ERA with 25 strikeouts over his past four starts, three of which led the Mets to a win.

We have two pitchers motivated to do well, as they are both in the thick of the playoff race; hence we like this one to go under. The total has gone under in 3 of Syndergaard's last 4 starts. The under is 3-0-1 in Civale's last 4 starts.