Schumacher (1-0) was in control for most of the evening, scattering six hits while walking just one and striking out six of the first 10 hitters he faced to allow his club time to establish the upper hand.
Shannahan got the job done on the hill late for the Bears to earn his first save of the year. The senior right-hander entered in the eighth inning with the tying run 90 feet from home and promptly retired Carter Burgess on a ground ball before closing out the decision with a pair of strikeouts in the ninth.
Missouri State took advantage of a touch of wildness from Sam Houston State starter Cody Dickson to build an early three-run lead. After issuing a walk to Dylan Becker to start the game, Dickson unloaded a two-out wild pitch to allow the Bears' second baseman to score with the game's first run.
The Bears came up with another two-out tally in the third after Tate Matheny drew a base-on-balls, moved to second on a Travis McComack sacrifice and scored when Keenen Maddox lined a double down the left-field line. Dickson put both Becker and McComack on to begin the fifth, and Luke Voit would make the Bearkats pay by driving an RBI single to center for a 3-0 Bears' advantage.
Sam Houston State (0-2) finally broke through against Schumacher in the sixth courtesy of a Ryan O'Hearn RBI single that scored Luke Plucheck and snapped the Bears' string of 16 1/3 consecutive innings without allowing an earned run to begin the season. With Schumacher out of the game after a 109-pitch night, the Bearkats would gear up their offense in the eighth, striking for three straight hits to pull to within 3-2.
But Shannahan would relieve Zach Merciez and come up with perhaps the key out of the game by coaxing a bouncer to short off the bat of Burgess, who had hits in two of his previous three trips to the plate. Shannahan would give up a two-out hit to Colt Atwood in the ninth, but extinguished the Bearkats hopes by fanning Plucheck for the final out.
MSU, which was out-hit 10-3 by SHSU, drew seven walks on the night and got an offensive lift from Becker for the second day in a row. The sophomore infielder walked twice and scored two times--including the game-winner--against the Bearkats after driving in the go-ahead run in the Bears' 11-inning win over Texas State on Friday.
In addition to Burgess's two-hit day for the Bearkats, O'Hearn and Miller each went 2-for-4 with an RBI.
Dickson suffered the loss for the Bearkats after allowing all three MSU runs in 4.0 innings of work. Jason Simms came on to pitch valiantly, tossing four scoreless innings of one-hit ball to keep SHSU in the contest.
Missouri State will conclude play in the tournament Sunday with an 11 a.m. game against Tulane (1-1).