Samford scored seven of the first nine points in overtime.
In the final seconds of regulation, VMI's Bubba Parham made one of two free throws to give the Keydets a 70-68 lead, then Samford's Brandon Austin tied it with a layup.
Josh Sharkey added 15 points for Samford. Guerrero also had 12 rebounds and three blocks for the Bulldogs, while Sharkey posted nine assists.
Myron Gordon had 12 points for Samford (15-11, 5-8 Southern Conference).
Jake Stephens had 15 points for the Keydets (7-17, 1-11), whose losing streak stretched to five games. Bubba Parham added 15 points, seven assists and six rebounds. Garrett Gilkeson had 13 points, 14 rebounds and seven assists.
The Bulldogs improve to 2-0 against the Keydets this season. Samford defeated VMI 96-68 on Dec. 29.
Samford matches up against Chattanooga at home next Saturday. VMI takes on Wofford on the road on Thursday.
For more AP college basketball coverage: https://apnews.com/Collegebasketball and http://twitter.com/AP-Top25
Elements of this story were generated by Automated Insights, http://www.automatedinsights.com/ap, using data from STATS LLC, https://www.stats.com
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