Booker made a pair of free throws with 3:17 left in overtime and Long Beach State never trailed again.
Jordan Gilliam's 3-pointer with 22 seconds left in regulation tied the game at 59-all and both teams missed their final shot attempts to send it into overtime.
Booker missed 11 of 14-shot attempts from the field but was perfect from the foul line and made 10 of the 49ers' (11-18, 5-8 Big West Conference) 18 free throws. Bryan Alberts added 16 points for Long Beach State.
Callum McRae led the Highlanders (9-19, 3-9) with 16 points and 10 rebounds, Gilliam scored 15 and Dikymbe Martin scored 14. The Highlanders made just 1 of 2 from the foul line and settled instead for 26 3-point attempts in which they converted eight.
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