McCarthy broke the tie in the bottom of the third with three runs and would lead for good.
After Mosley starter Andrew Perdomo, who entered the game with a perfect 9-0 record and 0.95 ERA, walked Blade Bielski and Quintana to start the inning, to the surprise of many Mosley coach Todd Harless pulled Perdomo off the mound in favor of Joey Hair.
Gigliotti laid down another perfect sacrifice bunt to advance the runners and No. 3 hitter Brandon Vicens brought them both home with a towering shot off the green monster wall for a double. He then caught Hair napping and stole third, which paid off when Gonzalez launched a deep fly ball to center, allowing him to tag up and score.
Nuñez, who went the distance and scattered seven hits along the way, was steady through the first four innings but dodged a major bullet in the fifth.
With a runner on first and two outs, he gave up a base hit to leadoff hitter Jordan Larry, balked and then hit Brady Bell to load the bases. Bowen McGuffin then stepped up and hit a laser right at left fielder Bigliotti, who coolly gloved it for the final out.
The Mavericks added their last run in the sixth after Vicens led off with a double and eventually scored on a sacrifice fly to left off the bat of Aaron Soto.
Gigliotti, the teams left fielder, made a spectacular late inning horizontal diving catch of a drive that would have scored two runs and put them behind in what turned out to be a 7-6 regional semifinal victory over Mater Academy two weeks ago. That was perhaps the defining postseason moment for the Mavericks, who overcame a 5-0 deficit in that game or it well could have been Mater out in that dog pile instead.
It feels great to have made such a big play, but our team had plenty of big plays along the way that if they dont make those, then mine wouldnt have meant anything, Gigliotti said. We still had to keep playing after that in order to reach this moment.
WP: A. Nuñez (5-2). LP: A. Perdomo (9-1). Top performers: J. Quintana 2-2. B. Vicens 2-3, 2 RBI. B. Gonzalez 1-2, RBI