From the beginning, it didn't appear as though OU would have the kind of trouble it did in the first half.
They extended their lead to six on a couple of occasions and even seven moments later when Hand hit another three at the 14:28 mark.
But that's when Tech woke up, scoring 10 unanswered to take an 18-15 advantage of its own.
The Red Raiders led by as much as five in the first half.
Teams then rode the teeter totter for the remainder of the first half, as the Red Raiders carried a 28-26 lead into intermission.
The Sooners were down at the break in large part due to a poor 28.6 percent field goal percent, while the visitors, on the other hand, converted 52.4 of their attempts in the opening frame.
That didn't change much in the second half, as the Red Raiders outshot the Sooners 47.9 percent to 32.2 percent in the contest, but turnovers and free throws were the main story in this one.
The Sooners committed only 15 to 25 by the Red Raiders, and they made 24-of-30 free throws, while Tech only attempted 16, though they made 13 of those.
With that, the Sooners used a 7-0 spurt to start the second half and lead 33-30.
They'd never trail again.
The lead was nine just inside the 10-minute mark, 11 at the eight-minute mark, and OU moved it to 13 when Ellenberg hit a pair of free throws with 7:03 remaining, a fraction of an 8-of-9 performance from the charity stripe in the contest.
Although Tech briefly cut the deficit back to single digits a couple times down the stretch, the Sooners still coasted to victory in the final seven minutes.
Along with Ellenberg, three other Sooners finished in double figures, as Robinson, Hand and forward Carlee Roethlisberger finished with 16, 14 and 11, respectively.
Center Kierra Mallard led the way for TTU with 21 points, while guard Chyna Brown added 17.
OU next faces Kansas at 12 p.m. CT Sunday in Lawrence, Kan., where it will attempt to improve upon its 4-0 Big 12 Conference record.