Dellavedova sank five 3-pointers while also providing six rebounds and four assists for the 11-seeded Gaels (28-6), who now move to play sixth-seeded Memphis Thursday in Auburn Hills, Mich.
Stephen Holt helped out with 18 points in the victory.
Middle Tennessee (28-6) was paced by Marcos Knight with 16 points.
Neiko Hunter and Kerry Hammonds each added 10 in the loss.
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