Okaro White (10 points) sealed the win on a basket with 14 seconds left, allowing the Seminoles (8-3) to hang on at the Orange Bowl Basketball Classic.
Aaron Thomas provided 18 points and six rebounds for FSU.
The Minutemen (10-1) fell for the first time this season as leading scorer Chaz Williams was limited to 10 points on 4-of-14 shooting.
Derrick Gordon netted 12 and Cady Lalanne had a double-double of 10 and 15 rebounds for UMass.
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