Haase hit a career-high five 3-pointers, Alvarez grabbed eight rebounds and had a career-high nine assists, and Cummings was 5-of-7 shooting. James Glisson III added 14 points for Mercer (2-0).
Rodney Howard hit a jumper that gave Georgia Tech (0-2) a 4-2 lead but Cummings made a 3-pointer 30 seconds later to spark a 10-0 run and the Bears never again trailed.
Georgia Tech, which went into halftime trailing 38-35, committed five turnovers and made just 2 of 16 from the field over the first 10-plus minutes of the second half as the Bears stretched their lead to double figures when Alvarez converted a three-point play that made it 51-41. The Yellow Jackets twice hit 3-pointers to trim their deficit to seven points, but got no closer.
Mercer shot just 44% (27 of 61) from the field, compared to 46% (28 of 61) shooting by the Jackets, but hit 12 of 25 from behind the arc and 17 of 18 from the free-throw line.
Georgia Tech, coming off a four-overtime loss to Georgia State in its opener, got off to a hot start but appeared to run out of gas. The Yellow Jackets shot 56% in the first half.
The Bears have won two in a row against Georgia Tech, but just 17 in the 45-game series. The teams last met December 22, 2011, a 65-59 win by Mercer.
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