NEW YORK -- The first pitch Mark Vientos saw from Justin Wilson in the 10th inning was a cutter inside, out of the strike zone. That's all it took for New York Mets manager Carlos Mendoza to know how the at-bat would end.

"The way he took it, I was like, 'Game's over here,'" Mendoza said.

Mendoza saw there was no panic. Vientos wasn't rushed. He seemed at ease.

Moments later, on the eighth pitch of the duel, Vientos proved Mendoza's hunch right, launching a 97 mph fastball for a walk-off, two-run home run to give the Mets a 6-4 win against the Cincinnati Reds.

The victory was the Mets' season-high eighth straight, keeping them in a tie for the final NL wild-card playoff spot with the Atlanta Braves, who also won Friday. Both teams are 77-64 with 21 games left, including three against each other in Atlanta later in the month.

"I was ready to swing at that first pitch and I saw it pretty good," Vientos said. "And I kind of felt the same way. I was like, 'OK, I see him well.' And I think Mendy said it perfectly. I saw him good and then my game plan was, like I said, to put barrel to ball."

It was Vientos' second home run of the night and second walk-off homer of the season. The first walk-off came against the St. Louis Cardinals on April 28, when Vientos was still playing to prove he belonged on the roster. It was just his second game in the majors this season after starting in Triple-A, losing out to Matt Baty for the starting third base job in spring training. He entered the game as a pinch hitter and hadn't yet started a game for the Mets. Two days later, he was optioned back to Syracuse.

Vientos, 24, returned to the majors May 15 to start at third base and hasn't relinquished his spot. He is slashing .289/.342/.563 with 24 home runs and 62 RBIs in 91 games. His .905 OPS leads the streaking Mets -- and all major league third baseman with at least 350 plate appearances this season. So does his .563 slugging percentage.

He has become an indispensable power source for one of baseball's deepest lineups.

"It's hard to describe because he's been everything," Mendoza said. "It's just really cool and special to see someone that went through a lot early in the year [do that]."

The clubs alternated two-run bursts Friday. Vientos, batting third, put the Mets ahead with a two-run home run in the first inning against Fernando Cruz, the Reds' opener in their bullpen game. Elly De La Cruz matched him with a two-run blast in the fourth inning.

The Mets retook the lead in the sixth on RBI singles from Jose Iglesias and J.D. Martinez. Half an inning later, TJ Friedl chased Mets starter Sean Manaea from the game with a two-run home run with two outs in the seventh.

The ninth inning featured two brothers. On one side, Mets closer Edwin Diaz struck out the side to keep the tie intact. As he walked off the mound, his younger brother, Alexis Diaz, entered the game to try to match him. The younger Diaz -- Cincinnati's closer -- hit a batter but stranded the runner at second base to send the game to extra innings.

The stage was set for Vientos to give the Mets their longest winning streak since 2019.

"Proud of him," Mendoza said. "He's in a really good spot and he's enjoying playing the game and coming to the ballpark and just being around the guys in there."