Belmont led 50-40 with 8:13 to go. After Vanderbilt cut the lead to five, the Bruins went on an 11-4 run to make it 62-50 with 1:36 left in the game and the Commodores didn't threaten again.
Both teams struggled from beyond the arc.
Vanderbilt (1-1) was just 4 of 23 from the 3-point line and shot 34 percent from the field.
Belmont (1-1) made 6 of 27 shots from long range.
Saben Lee had a team-high 19 points for Vanderbilt, and Jeff Roberson added 13 points and 12 rebounds.
Windler made 9 of 15 shots from the floor, grabbed 11 rebounds and had two steals for the Bruins.
Belmont shot 40.7 percent from the floor and held Vanderbilt to 13.6 percent shooting from 3-point range three days after it allowed Washington to shoot 53.8 percent from the floor in an 86-82 win over the Bruins.
Egekeze scored eight points during a 10-2 Belmont run that put the Bruins up 16-13 midway through the first half.
After the Commodores tied it, the Bruins responded with seven straight points, five of them by Egekeze.
Vanderbilt, which doesn't leave Nashville for the season's first eight games, hosts North Carolina-Asheville on Friday and No. 10 USC on Sunday.
Belmont plays at Middle Tennessee on Thursday.