Centre (3-1) shot the ball well, hitting 13 of 22 3-point shots and 16 of 19 free throws. The Colonels also committed a season-low 14 turnovers; they averaged 20.7 turnovers in their first three games.
Atwell had six assists along with his 20 points in what Mason said was one of his best games.
"He really let the game come to him," Mason said.
James Booker added 17 points in only 15 minutes, contributing strong 3-point shooting to the Colonels' cause, and Mason said freshman Matt Jacobson added a spark off the bench.
The game began a stretch of four games in eight days for the Colonels. Their next is Tuesday at home against Transylvania.
Thomas More 56, Centre 31 - At Crestview Hills, Centre sank just 10 baskets, turned the ball over 26 times and gave up two rebounds to every one it got in losing to host Thomas More in the first round of the Julie Costello Memorial Tournament.
"It was really not a good day on either end of the floor for us," Centre coach Jennifer Ruff said.
Ruff said the rebounds hurt Centre (2-2) most. The Colonels were outrebounded 52-26, and they gave up 28 offensive rebounds.
"We held them to a low percentage, but they capitalized off their rebounds," Ruff said. "This team really went to the boards hard."
While Thomas More (3-0) shot 34.2 percent from the field, Centre shot just 27.8 percent overall and 23.5 percent in the first half, when the Colonels went 4-for-17 and scored only 10 points.
"We didn't shoot the ball well. Give credit to Thomas More and their defense for really forcing us into some bad shots," Ruff said.
Jacqueline Coleman led Centre with seven points and five rebounds off the bench. The Colonels' starting five combined for only 15 points, including six each from Virginia Lowery and Casey Geiman.
Centre plays for third place today against Emory, which lost 73-59 to Westminster (Pa.).