Rams sophomore Alycia Horner went the distance, holding Smithsburg to single runs in the fourth, fifth and seventh innings.
Southern took a 1-0 lead in the second when Kendra Hardesty singled to center, took second on a wild pitch, moved to third on a throwing error and scored on a bunt by Lindsay Lipscomb.
Smithsburg tied the score in the fourth when Cara Ferguson tripled to center and scored on a bunt by Kinsey Shifflett.
The Rams snapped the tie with four runs in the fifth inning to take the lead for good.
April Sisler led off with a single to left, took second on a groundout and scored on a single to left by Kelsi Graham. After Ayla Palmer singled to right, Horner helped herself with a single to center to drive in Graham. Lyndsey Gladfelty knocked in Palmer with an infield single and Horner also scored on the play after a throwing error.
Smithsburg got a run in the bottom of the fifth when Shayla Murray scored on a single to center by Brooke Parks.
The Leopards reduced the deficit to 5-3 with a run in the seventh when Karah Knight scored on the front end of a double steal attempt. Horner shut the door after that.
Katie Sprecher hit two doubles and Murray added two hits for Smithsburg.
Palmer had three hits, while Graham and Sisler added two hits each for Southern Garrett.
"We're very proud of our two seniors, Kayla Wastler and Paige Decker," Barnhart said. "They always played hard and set a good example for the younger players. The younger players will remember that for years to come."
Southern Garrett 5, Smithsburg 3
So. Garrett 010 040 0 -- 5 10 0
Smithsburg 000 110 1 -- 3 9 4
Horner and Gladfelty. Ferguson, Decker (5) and Shifflett. WP -- Horner. LP -- Ferguson (5-1).