DENVER – Richmond added another upset to an impressive NCAA tournament resume that already has several.

And Vanderbilt exited early — again.

Kevin Anderson scored 16 of his 25 points in the second half, including a game-sealing floater with 18.7 seconds remaining, to lift 12th-seeded Richmond to a 69-66 win over No. 5 seed Vanderbilt on Thursday in the Southwest Regional.

The Spiders (28-7) sprang the second upset of the day at Pepsi Center after tiny Morehead State, the 13th seed, used a 3-pointer by Demonte Harper in the waning seconds to beat fourth-seeded Louisville 62-61 in the early game.

But while Morehead State players fell on the floor, writhing in the celebration, the Spiders simply shook hands and walked to the locker room. This hardly counts as a shocker, especially considering their March history.

Richmond beat an Auburn team led by Charles Barkley during the 1984 NCAA tournament and picked off second-seeded Syracuse in 1991.

This is the Spiders’ first NCAA tournament win since they beat South Carolina in 1998 as a No. 14 seed, but the reputation has been cemented.

Maybe that’s why this win didn’t seem like that big of a surprise for the Atlantic-10 tournament champions, who were only a three-point underdog to the Commodores of the Southeastern Conference.

Justin Harper added 13 points and Francis-Cedric Martel contributed 12 as the Spiders won their eighth straight game.

“A very gutty effort by our team,” Richmond Coach Chris Mooney said. “I thought our poise and veteran leadership really showed through in this game.”

Vanderbilt had a chance to tie with 2.5 seconds left, but Rod Odom’s desperation heave was nowhere near the basket as time expired.

So much for the Commodores (23-11) vanquishing their tournament demons. They now have stumbled in their last three appearances in the NCAAs, also losing to No. 13 seed Murray State on a last-second shot last season and falling to Siena, another 13th seed, in 2008.

They thought this could be the team to end the drought.

But the Commodores hurt themselves by never finding an answer for Anderson, who made 4 of 9 from 3-point range to take control of the second half.

“My teammates did a good job of finding me,” Anderson said. “I was in the zone.”

Vanderbilt center Festus Ezeli and John Jenkins, the SEC’s leading scorer, each finished with 21 points.

“They just got hot,” Jenkins said. “We tried our best to contest shots, but they jumped up and made them. That’s all I can think of.”

Trailing 48-39 early in the second half, the Spiders worked their way back into the game behind the shooting of Anderson, the league tournament MVP. He hit three straight 3-pointers at one point during a 12-0 run to give Richmond a 51-48 lead.

Brad Tinsley finally broke the dry spell for Vanderbilt with a short jumper. The Commodores went more than 4 minutes without a basket.

Vanderbilt tied the game at 55 on a 3-pointer by Tinsley with 8:15 remaining, but Richmond took the lead for good on two free throws from Harper.

Just when it looked like the game was all but over, Richmond kept Vandy’s hopes alive.

With Richmond up 68-65 and 5 seconds left, Darrius Garrett went to the line to secure the win. But he missed and Harper fouled Ezeli underneath the basket.

Ezeli made the first free throw and intentionally clanged the second, the ball skittering into the corner where Anderson tracked it down. He was fouled and made 1 of 2 to restore a three-point lead.