Although MCHS had defeated Summit 7-2 in their lone regular season encounter, the Spartans were coming off a stunning 3-2 upset win over top seeded Page in the tournament semifinals two days early and jumped out to a 3-1 lead midway through the first half of Thursday's contest.
The Tigers, however, didn't panic and narrowed the gap to 3-2 at the break before tying the game at 3-3 midway through the second half.
"This feels great because a lot of hard work has paid off. The kids have really put in a lot of work this season and it's good to see them achieve one of their main goals," said Marshall County coach Lisa Raffo. "We've been a second half team the entire season and I reminded them of that at halftime. They took that to heart and did what they were supposed to do."
Acosta finished the game with three goals and an assist and has now found the back of the net 38 times this year, which is a single season school record. Brad Pippen also tallied a goal for MCHS, while Ivan Leyva dished out three assists.
Aided by their second half surge, Marshall County outshot Summit 16-14 overall, while Tiger goaltender Jonathan Salinas recorded 10 saves.
Bret Thomas notched two goals to lead the Spartans offensive attack. Austin Gwinn also added a goal and an assist for Summit, while Cody Allem and Dylan Chambers each registered one assist.
MCHS got off to a promising start and took a 1-0 lead five minutes into the contest when Acosta blasted a 10-yard shot past Spartan goalie Cody Thorton after receiving a pass from Leyva on the left side of the field.
The Tigers lead would prove to be short lived, as Thomas took a crossing pass from Gwinn in front of the Marshall County net and hammered home a shot from point blank range to tie the game at 1-1 in the seventh minute.
Thomas then put Summit up 2-1 in the 21st minute by lining another close range shot into the left corner of the net after receiving a pass from Allem in the middle of the field.
The Spartans stretched their lead to 3-1 a few moments later when Gwinn scored on a header off a corner kick play in the 22nd minute.
Acosta finally stemmed Summit's momentum in the 30th minute by heading in a crossing from Leyva to whittle the deficit to 3-2.
The Tigers failed to cash in on several scoring chances over the next 18 minutes before Pippen converted on a header attempt in the 59th minute to knot the game at 3-3 after receiving a throw in from Acosta in front of the Spartan net.
In the 75th minute, the Spartans nearly pulled back ahead, but Salinas made a nice running catch on a close range shot by Thomas to maintain the stalemate.
Acosta then scored the decisive goal in the 77th minute when he took a pass from Leyva in the middle of the field and fired a low, skidding shot into the left side of the net before MCHS burned off the final three minutes to hold on for the 4-3 victory.