UCF was steady in the first half against Texas Tech, then dominated early in the second to roll into Lubbock and open Big 12 Conference play with a gritty 87-83 triumph on Tuesday.

Darius Johnson knocked two free throws with 19 seconds to go and another with 9.2 seconds left to help the Knights win their sixth straight game, staving off the Red Raiders’ furious rally from an 18-point second-half deficit.

Playing for the first time since late November due to a knee injury, JT Toppin delivered 26 points and 10 rebounds for the Red Raiders (9-3, 0-1), with Chance McMillian and Federiko Federiko chipping in with 12 points each.

Johnson led UCF with 24 points, while Keyshawn Hall was big for the Knights (10-2, 1-0) on his way to a 22-point, eight-rebound performance. He scored 17 in a near flawless first half when his team plowed in front 47-41.

The Red Raiders notched the first two points after halftime, then went cold. That allowed UCF to reel off a 14-2 run that ended with a 61-45 cushion on Johnson’s fastbreak layup.

The lead swelled to 71-53 with 10 minutes left before Texas Tech embarked on a comeback bid. McMillian supplied five points in an 11-0 surge over 2:20 that closed the gap to 71-64 with 7 1/2 minutes to go.

Johnson halted the run with a pair of free throws which put the Knights back up by eight, and that lead persevered even when the Red Raiders made a late lunge. McMillian’s second-chance 3-pointer got his team within 82-78 with 2:52 left in the game, then Toppin’s follow jumper got Texas Tech within 84-83 with 37 seconds left before Johnson iced the win.

UCF grabbed the halftime lead with hot shooting — 57.1 percent overall (16 of 28) and 6 of 14 (42.9 percent) from 3-point territory. Hall led the way by hitting all seven floor shots, including three 3s.

Perimeter shooting was a problem for Texas Tech. The Red Raiders made only three shots from beyond the arc in 16 attempts (18.8 percent), while UCF finished 10 of 23 (43.5 percent).