Adbert 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.
Javier Baez homered and tripled, and Anthony Rizzo had a two-run double as the NL Central leaders improved to 26-12 at Wrigley Field.
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.
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.
Baez hit his 18th homer in the seventh.