Alexander made 13 of 15 free throws. He added eight rebounds.
Mitch Ballock had 11 points for Creighton (8-2), which earned its fourth consecutive win.
The Bluejays forced a season-high 20 turnovers.
Creighton dominated the first half and led 45-24 at the break. The Vaqueros' 24 points in the first half were a season low for the team.
Creighton faces Oklahoma at home on Tuesday. Texas Rio Grande Valley takes on Nebraska Omaha on the road on Sunday.
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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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