The Dodgers made history when they opened the season with eight straight wins, something no reigning World Series champion had ever done. But they’ve been just a shade above mediocre since then.

“I wouldn’t say [I’m] worried. It’s kind of where we’re at right now,” manager Dave Roberts said.

“It’s been hard to gain traction.”

If anything, the Dodgers have been spinning their wheels. Because with Wednesday’s 6-1 loss to the New York Mets, the team’s third loss in four games, the Dodgers fell to .500 over the last month and their lead in the National League West remained at just a game over the San Diego Padres heading into Thursday’s get-away day matinee with the Mets.

Since their historic start, the Dodgers have had just three winning streaks of more than two games, but three losing streaks of more than two games. For every three steps forward, the team has taken 2 ½ steps back.

And while the Dodgers entered Thursday with the fourth-best record in the league, over the last two months they have a lower winning percentage than the Milwaukee Brewers, the third-best team in the Central Division. The reason why, Roberts said, is pitching.

Or rather the lack of pitching.

The staff ERA in May was 4.39; only four teams in the National League were worse. The ERA is just a tick lower four games into June.

“Teams win consistently over stretches — as far as winning streaks — by preventing runs,” said Roberts, whose team had three shutouts in the first 23 games but hasn’t had one since. “It’s hard to do that without it. So for us, it’s just getting a quality start, then have good innings out of the pen.

Mookie Betts fields a grounder in the first inning.

(Gina Ferazzi / Los Angeles Times)

“If you look at the last few weeks, we just haven’t been able to do that. And that’s kind of the reason we’ve played .500 baseball the last few weeks.”

Take Wednesday as an example. Starter Tony Gonsolin lasted just five innings, giving up three runs, all in the first inning. Two came on a Pete Alonso homer. But at least Gonsolin, who was making his seventh start since returning from Tommy John surgery, was able to take the mound. The Dodgers have 15 other pitchers on the injured list.

“Just threw a bad one to Pete, and he didn’t miss it,” said Gonsolin (3-2) of the home run, Alonso’s 13^th of the season and the first of two on the night. “That was my least favorite [pitch] of the outing, for sure.”

The bullpen didn’t fare much better. After a pair of hitless innings from Anthony Banda and Lou Trivino, Ryan Loutos hit the first batter he faced in the eighth, walked the next, then gave up a three-run homer to Alonso, who finished with a season-high five RBIs.

The Dodgers’ only run came on Andy Pages’ solo homer, his 12^th of the season, with one out in the ninth. The hit was Pages’ third of the night — half his team’s total. He also had a second-inning infield single and a seventh-inning double, extending his hitting streak to a season-high nine games and raising his average to .290.

For the Mets, starter Griffin Canning (6-2) cruised through his six innings, facing just four batters over the minimum. The former Angel gave up three hits, walked one and struck out seven in his best outing of the season, winning for the first time in nearly a month.

And that left the Dodgers struck in a rut, searching for enough traction to get themselves out.

“We know we’re not playing the way we started,” outfielder Michael Conforto said. “We’ve been a little bit banged up. A lot of the pitchers are banged up. And even a lot of our our position players are working through some stuff. So there’s a bit of that.

“And then there’s just the lack of coming through in big spots, myself included in that. But obviously we understand who we are and what we can do when we’re clicking on all cylinders.”

Etc.

Relievers Kirby Yates (hamstring) and Michael Kopech (shoulder) both threw short simulated games Wednesday and Roberts said both are close to being activated. Kopech gave up 11 runs in 6.1 innings while on a rehab assignment in Oklahoma City. Kopech’s last big-league appearance came in the fifth and deciding game of last fall’s World Series.