Guadarrama had 17 points for the Wildcats (9-9, 2/3 America East Conference).
UMBC rallied from a 28-16 halftime deficit.
A 14-2 run pulled the Retrievers within 55-50 with just under four minutes to play. Still down five with under two minutes to play, K.J. Jackson hit 3 of 4 free throws and Keondre Kennedy nailed a 3-pointer to cut the deficit to 59-58 going into the final minute.
The teams traded baskets Chris Lester scoring for the Wildcats with 34 seconds to go, R.J. Eytle-Rock answering for UMBC at 23.9 seconds before Guadarrama secured the win.
Jackson scored a season-high 22 points and had nine rebounds for the Retrievers (7-12, 0-4), whose losing streak stretched to four games. Brandon Horvath added 14 points and Eytle-Rock had 12 points.
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This was generated by Automated Insights, http://www.automatedinsights.com/ap, using data from STATS LLC, https://www.stats.com
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