Euphoria and heartbreak are on opposite ends of the emotion spectrum, and sometimes in postseason play they appear on opposite ends of the soccer field as well.

No. 10 South Side scored twice in a 38-second span to beat No. 3 Mineola, 3-2, in the final three minutes of a Nassau Class A boys soccer semifinal Friday night at Adelphi’s Motamed Field. Tears were shed on both benches afterwards as the Mustangs came to grips with their final loss and the Cyclones attempted to fathom how they stormed back to earn a championship date with No. 1 Glen Cove.

“I can’t even explain the way I’m feeling right now,” said Thomas Doyle, whose goal with 1:42 remaining was the winner. “It’s insane.”

Ryan Prendergast, who tied the game at 1 in the first half, took a ball down the left side and crossed to Doyle inside the 18-yard box. Doyle beat a defender and deposited a shot in the bottom left corner 38 seconds after Robert Reis tied the game for South Side on a rebound off the post.

It all happened after Mineola’s Erick Marquez set up Luis Tinoco’s go-ahead goal in the 72nd minute.

advertisement | advertise on newsday

“If you really break it down,” said South Side coach Fred Paul, “those last two or three minutes it was chaos but it was calm at the same time. That second goal hit off the post and you have to have the composure to tie it, and the winning goal was beautiful. He was well-composed and put that ball in the corner.”

The Cyclones (11-3-4), who won the 2014 county title, lost to Glen Cove, 2-1, in the regular-season finale.

“I’m excited,” Doyle said. “They beat us 2-1 this season, but that doesn’t affect us. We’re not scared to play them. We’re ready.”

Glen Cove 4, Plainedge 0: As Hernan Cruz stepped up to take a free kick in the 12th minute Friday, there was little reason to believe he would score.

The senior had not scored all year and the ball was marked about 35 yards from the net. But with a strong kick and a gusting wind at his back, he provided perhaps the most important goal in Glen Cove’s season.

Glen Cove developed a well-deserved reputation as an offensive juggernaut in the regular season — 42 goals in 14 games — but that prowess had not translated into postseason output. Through two rounds of the Nassau Class A boys soccer playoffs, the Big Red had one goal and a victory on penalty kicks to its name.

Then Cruz delivered a perfect strike into the top left corner at Adelphi’s Motamed Field. That opened the floodgates and the No. 1 Glen Cove advanced into the county championship with a 4-0 win over No. 4 Plainedge. Cris Henriquez (eight saves) posted his eighth shutout.

Glen Cove (18-0) will face the winner of No. 3 Mineola and No. 10 South Side Wednesday at Hofstra. The Big Red will be seeking their first county title since 1967.

“I was just trying to put [the free kick] in the net,” Cruz said.

“It was a relief,” coach Brian Smith said, describing Cruz’s goal. “You wonder where that first goal’s going to come from. Once that goal went in, we were able to settle and compose ourselves and play our game.”

advertisement | advertise on newsday

Seven minutes later, Glen Cove passed effectively through the midfield. Jelson Bonilla emerged with the ball on the right side and dribbled down toward the corner. His dangerous cross pulled Justin Lubitz (six saves) out of goal, opening the net for Alex Cota’s header that doubled the Big Red’s lead.

Niko Vidal headed in a rebound in the 50th minute and Jhecsson Garcia capped the scoring in the 69th minute.

“We can all play and we can all touch so we trust each other,” Bonilla said.

Glen Cove’s players have prided themselves on their cohesiveness as a unit all year. That the team had four different goal scorers Friday is proof their selfless, team style did not suffer after leading scorer Delwin Hernandez (eight goals) left to tryout for San Lorenzo de Almagro in Argentina three weeks ago.

“We’re happy for Delwin — he’s one of us,” Bonilla said. “We just came through as a team. Even without Delwin, we’re still a team. We have the players to win this.”