Samuel had 10 points and 11 rebounds for his sixth double-double this season for TCU (8-2).
Avery Sullivan had 14 points and 13 rebounds for the Cardinals (6-5), and Davion Buster had 14 points with four made 3-pointers. T.J. Atwood, a preseason All-Southland selection who averaged more than 17 points per game, finished with a season-low three points.
Edric Dennis Jr. scored all 14 of his points in the first half for TCU. R.J. Nembhard had 13 points and seven rebounds.
Dennis was 4-of-5 on 3's. He had eight points in less than 2 minutes, on two 3's and a breakaway dunk, as part of a 19-1 run for TCU that stretched over 9 minutes.
That was part of a bigger spurt after Lamar led 14-12 about 7 minutes into the game. The Horned Frogs closed the half on a 29-5 run for a 41-19 lead. The Cardinals were 1-of-12 shooting in that span and shot 33.3 percent (19 of 57) overall.
Lamar: The Cardinals have lost four consecutive road games, including an 81-56 loss at No. 8 Kentucky on Nov. 24. TCU and Kentucky were the only major conference teams on Lamar's schedule. The Cardinals wrapped up non-conference play.
TCU: The Horned Frogs play only twice over the next 19 days, with home games against No. 23 Xavier on Dec. 22 and George Mason on Dec. 30 before opening Big 12 play. The Horned Frogs' two losses have been by a combined four points but they haven't played a ranked opponent.
The 12th meeting between the two schools was the first since 2010-11 when TCU was still a member of the Mountain West Conference. The Horned Frogs are 10-2 all-time against Lamar, including 9-0 at home.
Lamar: The Cardinals return home to open the Southland Conference schedule against Southeastern Louisiana on Wednesday.
TCU: The Horned Frogs host Xavier as part of the inaugural Big East/Big 12 Battle next Sunday.
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