Lander improves to 20-3 overall, while Newberry slides to 15-10.
Jones improve to 4-0 after striking out four and allowing just six hits in nine innings.
Davis Funderburk (0-1) suffered the loss for Newberry with two strikeouts, four walks and four earned runs on two hits in three innings.
Newberry gained an early 2-0 lead in the second inning on Brandon Sheridan's two-RBI triple that plated D.J. Martinez and Nolan Schrenker.
The Bearcats took a 3-2 lead in the third when Dunn hit a solo homer over the left field fence, and Lewis followed with a two-run shot to right field that drove in Patrick Grady. It was Lewis' ninth homer of the year.
For Lander, Dunn and Tyler Wilson each went 2-for-3, while Lewis was 2-for-5.