After the first four St. Mary's batters reached base, including a Roger Welch leadoff home run, Runkles locked in.
He left runners stranded at second and third in the first and fifth innings and labored with the bases loaded in the sixth and seventh before being lifted with one out in the last inning. Runkles (8-1) allowed four runs on five hits and struck out seven.
"I had a terrible day on the mound," Runkles said. "I think I was pitching in cruise control until I got into trouble. Then I started to worry about keeping my elbow in the right position and my mechanics when I got in trouble.
"I have to give my infield a lot of credit. Trey Cobb, George Everly and Chad Brashears made some great plays behind me."
Cobb and Everly combined to turn a critical double play with runners on first and second with none out in the fourth. Brashears stabbed a liner to force St. Mary's to leave the bases full in the sixth.
St. Mary's jumped off to a 2-0 lead in the first and maintained the advantage until Anthony Sowers connected for a two-run shot to right center field in the third. Courtesy runner Nathan Allison scored on a wild pitch to stake the Gaels to a 3-2 lead.
"We've been preaching for them to be looking for something to hit," Montedoro said. "(St. Mary's pitcher Ty Harmon) was getting tired. We just started waiting for his fastball and looking for pitches."
Goretti clung to the lead until the fifth when Runkles, Derrick Herman and Joe Widmyer hit consecutive singles off Harmon for one run. Reagon Clutz reached on an error to bring home another run.
The Gaels led 5-3 heading into the sixth but added three insurance runs, two on Widmyer's single, to ice the game. George Everly came on with the bases loaded in the seventh to pitch the final two outs to earn a save.