MILWAUKEE -- Despite the closed roof at American Family Field on Tuesday, the Brewers elected to set off fireworks every time one of their players hit a homer. On each occasion, smoke hung in the air for several minutes afterward, creating a haze in the building’s upper atmosphere.

By the time Max Scherzer walked off the mound in the bottom of the sixth inning, having allowed his highest run total as a Met, it was difficult to see from one end to the other. Three times in a row the fireworks erupted, as Scherzer gave up back-to-back-to-back homers for the second time in his career in a 9-0 loss to the Brewers.

Through two starts, Scherzer owns a 6.35 ERA -- a statistic that stings doubly given the plight of the rest of New York’s rotation. Scherzer’s co-ace, Justin Verlander, is on the injured list. Fourth starter José Quintana is there as well and won’t return until at least July. Fifth starter Carlos Carrasco experienced a significant velocity drop in his season debut.

But there may be no more important Met than the 38-year-old Scherzer, whose past four starts look like this:

Oct. 1, 2022 at Atlanta: 5.2 IP, 4 ER
Oct. 7, 2022 vs. San Diego: 4.2 IP, 7 ER
March 30, 2023 at Miami: 6.0 IP, 3 ER
April 4, 2023 at Milwaukee: 5.1 IP, 5 ER

Average them together, and that’s a 7.89 ERA. Scherzer has allowed 10 home runs in those four outings, after giving up 11 homers in his previous 22 starts.

But how is it happening? Why is it happening? Some possible factors:

Off-speed location

After allowing a two-run double to Brian Anderson in the third inning Tuesday, Scherzer recovered to get through the fifth without further damage. That changed with one out in the sixth, when he caught too much plate with a curveball to Rowdy Tellez, who bashed it over the right-field fence for the first of three consecutive Brewers homers.

Of note, Scherzer did not allow a home run on a curveball all last season.

The following batter, Anderson, also went deep when Scherzer hung a slider, which was reason for even more alarm. The slider has long been Scherzer’s most important pitch, generating a 46.4% whiff rate last season. This year, it’s down to 32% through two starts.

“It’s not the stuff,” Scherzer said. “I’m generating swings and misses, but I’m not having 'out' pitches. I’m not generating swings and misses with two strikes. I’m not generating strikeouts like I can.”

Garrett Mitchell hit the third consecutive homer off Scherzer, who hadn’t allowed three in a row since a 2017 start for the Nationals in Arizona.

“Having seen him before, you know what he’s got but it’s still hard to get anything off of him,” Anderson said. “I was just able to get some pitches over the middle of the plate.”

Velocity dip

Although Scherzer hasn’t experienced the same level of velocity decline as Carrasco, his average four-seam fastball is coming in about half a mile per hour slower than it did last season. Given that relatively small difference, and the fact that his velocity has creeped up in each of his last two outings (from an average of 92.7 in his final spring start to 93.4 on Tuesday), this is the least of Scherzer’s current concerns.

Some velocity decline is natural as pitchers age. A bit could still return in the heat of summer. What’s important is that Scherzer is healthy, as all parties involved insist.

“Max feels good physically and the stuff’s good,” manager Buck Showalter said, adding: “He’s a very easy guy to trust.”

Pitch timer

Throughout Spring Training, Scherzer experimented with different ways to use Major League Baseball’s new pitch timer to his advantage, resulting in what he has referred to as “turbo ball.” That takes a certain amount of effort, which -- as Carrasco noted on Monday -- can accumulate over the course of a start.

Asked specifically if he believes the pitch timer has diminished Scherzer’s energy levels, catcher Tomás Nido replied that “it’s really not the time to [use] any excuses.” Showalter, meanwhile, said that if Scherzer is feeling fatigued, it’s probably because the Mets’ offensive at-bats are going so quickly. They have not scored a run for 20 consecutive innings.

Scherzer agreed with Nido’s assessment that excuses are unwarranted. He plans to watch video before leaving Milwaukee to untangle the source of his struggles.

“It makes your head scratch,” Scherzer said. “I’ve just got to pitch better -- that’s it. There’s no other quote. There’s no other way to do it. Be accountable for what you are and get the outs when you need to get outs.”