NEW YORK – The Mets are fighting through an unfathomable freefall that’s their worst stretch since 2018, and now have turned to their top pitching prospect to jumpstart their corroding starting rotation.

Right-hander Nolan McLean responded by shutting down the Seattle Mariners, one of the strongest offenses in baseball, through 5 1/3 scoreless innings in Saturday’s 3-1 win at Citi Field. The 24-year-old allowed two hits, recorded eight strikeouts and provided a glimpse into why his highly-touted six-pitch arsenal can be so effective. 

He befuddled Mariners hitters with his patented curveball and elite spin rate that topped veteran pitcher Charlie Morton, whose spin rate leads all of MLB. McLean’s dominant effort helped the Mets get just their third victory in their last 17 games. McLean lived up to the hype in his successful major-league debut.

“Surreal,” McLean said. “I couldn’t have dreamed it up any better.”

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The Mets (65-58) will, of course, continue to lean on the rookie in their pennant race, but it didn’t have to come to this.

New York has the second-highest payroll in MLB with a sum of nearly $340 million, and it entered the season with legitimate concerns about its starting rotation. Rather than spending on brand-name starters, the Mets president of baseball operations, David Stearns, signed Frankie Montas to a two-year, $34 million pact, Clay Holmes to a three-year, $38 million contract, and Griffin Canning to a one-year, $4.25 million deal. 

Instantly, the rotation became the club’s greatest unknown. With all that payroll, and all that talent, the Mets still had roster holes. 

Montas and Sean Manaea started the season on the injured list, so the Mets’ Opening Day rotation consisted of Kodai Senga, David Peterson, Tylor Megill, Holmes, and Canning. Up until the middle of June, that quintet evolved into the best rotation in baseball, boasting a 2.83 ERA that led the majors. Then, in a series of significant blows that would alter the course of the Mets’ season, came the injuries to Senga, Canning, and Megill. The Mets were forced to rely on their pitching depth, and it didn’t go well.

Montas was the biggest disappointment, returning from the injured list to post a 6.68 ERA in seven starts before getting demoted to the bullpen this month. Holmes has a 5.10 ERA over his last 10 starts. No starter outside of Peterson has finished the sixth inning in the past two months. Since June 13, Mets starters have combined to post a 5.34 ERA that’s ranked 26th in MLB in that span. As much as the rotation had been the club’s strength to start the season, some elements of its downfall were predictable.

Even on paper, it always seemed like the Mets didn’t have enough depth to cover them in case of injuries. The Mets ended the first half of the season by relying on arms like Huascar Brazoban, Chris Devenski, Brandon Waddell and Justin Hagenman to start games. Holmes, pitching in his first full season as a starter after being a reliever for the past six years, was certain to hit a wall at some point in the season. He blew past his career-high in innings pitched in the first week of June, and his ERA has only gone up since. 

Stearns, in his second year leading the Mets front office, focused on fortifying the bullpen at the trade deadline in hopes of offsetting the rotation’s struggles. The Mets acquired closer Ryan Helsley, submariner Tyler Rogers and reliever Gregory Soto to bolster the relief corps. While Rogers and Soto have performed mostly as advertised, Helsley has had a difficult transition. The former Cardinals closer has allowed nine runs (five earned) in 5 1/3 innings and seven appearances with the Mets. Stearns’ intention to create a super bullpen has not yet gone as planned.

Still, there is plenty of blame to go around for the Mets’ two-plus-month stretch of mediocre baseball. The offense, featuring a talented trio of Juan Soto, Francisco Lindor, and Pete Alonso, has largely been inconsistent. Since June 13, the Mets have a 98 wRC+ (two points below league average) that’s ranked 19th in MLB. In that span, the Mets have gone 20-34. Only the Nationals have been worse, and they fired both their GM and manager this season.

The Mets’ freefall has made the battle for the final National League wild-card spot the most interesting and competitive in baseball. After Saturday’s win, the Mets have a one-game lead over the Cincinnati Reds for that third spot, which figures to be their only remaining path into the postseason after squandering what was once a 5.5-game division lead to the first-place Philadelphia Phillies. 

All of which has led the Mets to promote a highly-touted prospect like McLean to help save their season. To be sure, calling up McLean was a necessary move, but there’s an argument to be made that it should’ve been done sooner. The Mets rotation has struggled for months, and now McLean needs to help carry the staff through a pennant race. That’s a lot of responsibility to place on his shoulders, even if delaying McLean’s call-up made him eligible to continue being a rookie in 2026.

Plus, the team’s upcoming schedule is daunting. The Mets are set to face the Phillies (seven games), Tigers (three games), Reds (three games), Padres (three games), and Cubs (three games) over the course of the next five-plus weeks. McLean’s ability to navigate the top offenses in baseball will certainly be tested. 

“Definitely something that maybe we’re missing,” Mendoza said of McLean’s performance. “Especially with how hard this stretch has been.”

It’s too soon to compare McLean to another Nolan, the great Hall of Fame pitcher Nolan Ryan, who began his storied career with the Mets. But the team’s luck started to turn after McLean’s fruitful debut. Things finally started going the Mets’ way on Saturday, including a seventh-inning Pete Alonso RBI double that he pulled just past the diving Eugenio Suarez at third base. In the past two weeks, plays like that have gone the other way for the Mets. 

A little spark in the form of a mid-August call-up might be just what the Mets need. The rotation reinforcement was way overdue, but at least it’s not yet too late. 

Deesha Thosar covers Major League Baseball as a reporter and columnist for FOX Sports. She previously covered the Mets as a beat reporter for the New York Daily News. The daughter of Indian immigrants, Deesha grew up on Long Island and now lives in Queens. Follow her on Twitter at @DeeshaThosar.

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