The loss is the end of the road for the Sooners, who end the year at 41-19.
ORU plated three runs on four hits in the first inning, as Smith initially gave up a single, hit by pitch and walk to load the bases.
Then, after a fielder's choice at the plate, first baseman Jared Schlehuber recorded a two-out, two-RBI single, and third baseman T.J. Bennett made it 3-0 on a single to right center.
That paved the way for Smith's exit after just 2/3 innings.
Lefty Dillon Overton ended the threat, but ORU did some more damage in the bottom of the second.
Thanks to a pair of Sooner throwing errors by catcher Tyler Ogle and second baseman Cale Ellis and two hits, three more Golden Eagles scored, making it 6-0.
ORU added one more in the fifth when another throwing error, this time by first baseman Cameron Seitzer and the Sooners' fourth of the game at that point, allowed second baseman Spencer Barnett to score.
In the meantime, the Sooner offense just couldn't capitalize on any of its opportunities, failing to plate a run in the contest.
The Sooners committed a total of six errors, equaling the number of hits they had.
ORU, on the other hand, played nine innings of errorless baseball, scoring its seven runs on eight hits.
Smith, who gave up those three runs on three hits in seven batters faced, took the final loss of the year for OU, while ORU's Drew Bowen was the winning pitcher.
ORU advances to play TCU, who lost 3-2 to Dallas Baptist in the winner's bracket game.
The Sooners will look to next year, when a lot of spots will likely need to be filled.