CHICAGO -- Whether rookie Adbert Alzolay stays in the majors for the remainder of the season is a question for another day.
The 24-year-old from Venezuela showed he belongs Thursday night.
Alzolay, the Cubs' top pitching prospect, tossed four innings of dazzling relief in his debut and the offense broke through with a six-run third as Chicago quickly rallied for a 7-4 victory over the New York Mets.
The crowd of 38,956 gave Alzolay a standing ovation as he headed to the dugout in the ninth, and he tipped his cap.
"The best thing that ever happened to me," he said. "All the people were cheering my name. I did my job, did my part and we got the game. ... It's amazing."
Rookie slugger Pete Alonso hit his 25th homer and Todd Frazier connected for the 200th of his career, but the Mets dropped to 15-26 on the road. Before the game, they fired pitching coach Dave Eiland and bullpen coach Chuck Hernandez.
Alonso tied Dodgers star Cody Bellinger (2017) for most homers by an NL rookie before the All-Star break. Alonso also is one shy of the Mets' rookie mark set by Darryl Strawberry in 1983.
Alzolay (1-0) replaced starter Tyler Chatwood to begin the fifth. The right-hander struck out five and didn't allow a hit until Frazier's leadoff homer in the ninth. Alzolay was replaced after walking the next batter.
He was recalled before the game from Triple-A Iowa, where he went 2-1 with a 3.09 ERA in six starts this season. Alzolay had 46 strikeouts in 32 innings with a WHIP of 0.94.
"It was nice for him to get called up," Rizzo said. "It was a long time coming; he was hurt last year. To pitch well like that at home, it's a good way to break in."
Steve Cishek got three outs for his seventh save.
New York spot starter Walker Lockett (0-1) retired his first six batters and had a 3-0 lead when he took the mound in the third following Alonso's two-run shot. But things quickly fell apart for the 25-year-old right-hander, who made his Mets debut in place of injured Noah Syndergaard.
Carlos Gonzalez led off with a single and was sacrificed to second by Chatwood. Daniel Descalso followed with an RBI single. Kyle Schwarber walked and Kris Bryant hit a bloop to right that fell in for a run-scoring single. With runners on the corners, Rizzo doubled down the right field line to score both and give Chicago a 4-2 lead.
The Cubs weren't done. Baez tripled to center to score Rizzo. After Lockett was yanked, Baez scored on a wild pitch by Brooks Pounders to make it 6-3.
"Lockett was cruising through it, throwing strikes, getting groundballs and then left a couple pitches up," Mets manager Mickey Callaway said. "He left a pitch up to Rizzo, he smoked it.
"It happened fast."
Baez hit his 18th homer in the seventh.
REGAN REPLACES EILAND
The Mets named Phil Regan interim pitching coach, Ricky Bones interim bullpen coach and Jeremy Accardo interim pitching strategist.
The 82-year-old Regan has been the club's minor league assistant pitching coordinator since 2016 after spending 2009-15 as the pitching coach for Class A St. Lucie. The former major league pitcher managed the Baltimore Orioles during the 1995 season.
Bones began this year as the pitching coach for St. Lucie. He was the Mets' bullpen coach from 2012-18.
Accardo was in his first full season as the Mets' minor league pitching coordinator.
"Our belief is we have the talent to be better than we've performed," general manager Brodie Van Wagenen said.
Alzolay said he was able to talk with his family in Venezuela after the game, and they were able to watch.
ONE FOR THE TROPHY CASE
Because of the Wrigley Field tradition of throwing back homers hit by visiting players, Frazier was easily able to retrieve the ball from his milestone shot.
Mets: To make room for Lockett, left-hander Daniel Zamora was optioned to Triple-A Syracuse.
Cubs: To make room for Alzolay, lefty Tim Collins was designated for assignment.
Mets lefty Jason Vargas (3-3, 3.74 ERA) faces righty Yu Darvish (2-3, 4.65) in the second of the four-game series Friday afternoon. Vargas had to leave his last start Sunday against the Cardinals after four innings with cramping in his left calf. Darvish is coming off his best outing of the season -- one run and two hits in seven innings against the Dodgers on Saturday.
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