Roberts shot 5 for 6 from deep. Phillips also had three blocks, while Williams posted seven rebounds.
Damon Wilson had 10 points for Georgia State (17-9, 10-5 Sun Belt Conference).
Corey Allen, who led the Panthers in scoring entering the contest with 15 points per game, shot only 20% for the game (1 of 5).
The Panthers swatted a season-high 10 blocks.
The Panthers improve to 2-0 against the Mountaineers on the season. Georgia State defeated Appalachian State 69-60 on Jan. 2. Georgia State matches up against Coastal Carolina at home on Saturday. Appalachian State matches up against Georgia Southern on the road on Saturday.
For more AP college basketball coverage: https://apnews.com/Collegebasketball and http://twitter.com/AP-Top25
This was generated by Automated Insights, http://www.automatedinsights.com/ap, using data from STATS LLC, https://www.stats.com
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