Stanton was on third with the bases loaded and two out in the bottom of the ninth of a scoreless season finale against the Detroit Tigers, who had been held hitless by Alvarez.
Known for his power, Stanton raced home with the winning run on Luke Putkonen's wild pitch to give the Marlins a 1-0 victory and Alvarez the fifth no-hitter in team history.
"I don't think I've been that excited all year, to be honest," Stanton said. "He might never have that chance to be in that situation again.
"I couldn't see (the wild pitch). I basically went off the crowd's reaction to my initial few steps because it went to the side of (catcher Brayan Pena), I thought he grabbed it."
Alvarez watched the winning play unfold from the on-deck circle, because he would have started the 10th inning if Miami failed to win the game in the ninth.
"I was nervous, anxious and hoping for a wild pitch," Alvarez said through translator/Marlins third base coach Joe Espada. "When I saw it, I got really excited."
Actually, it was the second time Alvarez celebrated the no-hitter. The first happened after he retired the Tigers in the ninth.
"At the time, I thought the score was 1-0, so I put my hands up," said Alvarez, who admitted being a bit surprised he hadn't been mobbed by his teammates. "Then I get to the dugout and Placido Polanco told me we haven't scored a run yet so the game is not over."
Alvarez, 23, was acquired from Toronto in the offseason and began the year on the disabled list with a shoulder injury. He took the mound hoping to end 2013 on a positive note and ended up striking out four, walking one and hitting a batter.
"I was focused to finish strong," he said, "but the no-hitter motivates me to work ever harder for next year."
The final day of Miami's 100-loss season began with news that longtime Marlins employees Mike Hill and Dan Jennings had been promoted to president of baseball operations and general manager, respectively.
Alvarez (5-6, 3.59), with some help, changed the discussion.
Detroit's Ramon Santiago lined out to a leaping shortstop
Adeiny Hechavarria in the third. Tigers starter Justin Verlander sent a fly down the right-field line that landed just out of Stanton's reach and barely foul in the sixth. In the ninth, Alvarez made two nice stabs of ground balls, the second being
Don Kelly's sharp hopper that might have gotten through the infield.
Through it all, the score remained 0-0.
With the crowd cheering on the Marlins in the bottom of the ninth, Stanton singled to center off Putkonen. He took second when Logan Morrison also singled.
"I got excited when I saw Giancarlo get that hit," Alvarez said. "I started praying, 'God, please give me a run here.' "
The runners each moved up a base on Putkonen's wild pitch with Hechavarria batting and one out.
With the infield in, Hechavarria grounded to short. Stanton, not running on contact, stayed at third.
"I really wanted to come through and give the game to Hendu and the team," Hechavarria said through Espada.
Next up was Chris Coghlan, who walked on an eight-pitch at-bat to load the bases.
"That was great place to be -- you get a hit and you make history," Coghlan said. "There isn't a cooler spot or more opportunistic time to bat. (Putkonen) gave me some pitches, I just fouled them off. It was great to be able to get the walk and give the big at-bat to Dobber."
Pinch-hitter Greg Dobbs stepped into that "great place" but never had a chance to become a hero -- Putkonen's first pitch bounced past Pena and allowed Stanton to score the winning run.
"That's how the Fish roll -- a walk-off no-hitter wild pitch," manager Mike Redmond said. "Why not finish the season in grand style with a sweep and a no-hitter. Wow."