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.
For more AP college basketball coverage: https://apnews.com/Collegebasketball and http://twitter.com/AP-Top25
This was generated by Automated Insights, http://www.automatedinsights.com/ap, using data from STATS LLC, https://www.stats.com
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