The Monmouth Academy Mustangs celebrate their Class C South regional championship in Standish on Thursday.

Monmouth Academy pitcher Cam Armstrong reacts Thursday after the Mustangs beat Lisbon High School for the Class C South regional championship. Armstrong allowed two hits while pitching a complete game.

Monmouth Academy pitcher Cam Armstrong pitched a two-hit shutout to win the Class C South regional championship against Lisbon High School.

Hayden Fletcher, left, of Monmouth Academy celebrates with Hunter Frost after crossing the plate to put the Mustangs up 1-0 during the first inning of the Class C South regional final against Lisbon High School in Standish.

Monmouth Academy head coach Eric Palleschi reacts during the seventh inning of Thursday's Class C South regional final against Lisbon High School in Standish.

Kyle Palleschi of Monmouth Academy crosses the plate to put the Mustangs up 4-0 during the fourth inning of the Class C South regional final against Lisbon High School in Standish on Thursday. Lisbon senior catcher Justin Le looks out into the field to follow the play.

Lisbon High School head coach Randy Ridley talks with Aidan Parker during a time out Thursday in Standish.

Lisbon shortstop Nick Ferrence fields a ground ball during the Class C South regional final against Monmouth Academy in Standish on Thursday.

Lisbon shortstop Nick Ferrence scrambles for a ground ball during the first inning of the Class C South regional final against Monmouth Academy in Standish on Thursday.

A Monmouth Academy line drive is out of reach for Lisbon High School shortstop Nick Ferrence during the fourth inning of the Class C South regional final in Standish on Thursday. Hayden Fletcher, right, of Monmouth Academy scored on the play to put the Mustangs up 5-0.