The Lady Vols have won 11 straight SEC games dating back to the loss here last season. They now have beaten Vanderbilt 25 times in the last 27 games in this series.
Bashaara Graves also had 16 points for Tennessee.
Vanderbilt (13-6, 3-3) lost for the first time at home this season and has lost three of four overall. The Commodores played without 6-foot-4 sophomore Clair Watkins, who tore her left anterior cruciate ligament in practice Wednesday. They still pulled down 21 offensive rebounds despite being outrebounded 46-43.
The Commodores managed to tie the score twice, the second time at 41 after scoring the first 12 points of the second half. The Lady Vols answered with an 11-2 spurt capped by a drive by Simmons with 12:45 to go, and Vanderbilt couldn't get closer than five the rest of the way. Tennessee hit 14 of 15 at the line in the final 3:49 to seal the victory.
The Commodores came in as the SEC's second-best team beyond the arc, shooting 36.4 percent from 3-point range. They shot 21.7 percent (5 of 23) and missed three 3s in the final minutes with a chance to make it a one-score game.
Tennessee had coach emeritus Pat Summitt sitting on the front row behind their bench right beside Tennessee Gov. Bill Haslam, just her second road trip this season. She watched the Lady Vols do what they usually do in Nashville. The Lady Vols now are 61-8 all-time against Vanderbilt in this in-state rivalry and 24-6 in Nashville.
Spani said having Summitt at the game meant the world.
"We were so excited when we found out she was coming, I was really trying to look for her, and I finally found her before the game," Spani said. "She brings inspiration to our team every time we see her."