What once seemed like a foregone conclusion is suddenly in jeopardy.

The Mets’ stunning slide now has them essentially eliminated from the NL East race and just two games ahead of the surging Giants for the final wild-card spot with 17 games left on their schedule.

While the Amazin’s own the tiebreaker over San Francisco, this team has done little over the past three months to inspire confidence.

It’s been nearly three full months since the Mets hit their high point of 21 games above .500 on June 12 and they owned the sport’s best winning percentage and a 5.5-game division lead.

Since that day, the Mets’ contemporaries are the Twins, Rockies and Nationals instead of the Dodgers and other powerhouses.

The Mets are nine games behind the Phillies in the NL East. AP

The Mets have the fourth-worst winning percentage in this span with their 31-45 mark, ranking ahead of just Washington (30-46), Minnesota (28-49) and Colorado (27-50).

None of those teams are even remotely close to a playoff berth.

MLB’s worst teams since play ended June 12

The Mets have also lost a staggering 14.5 games in the division in this brutal stretch, the biggest collapse of any team in the sport.

The Phillies trailed the Mets by 5.5 games through June 12, but now own a nine-game advantage.

Sean Manaea’s struggles have contributed to the Mets’ slide. Getty Images

Even the red-hot Brewers, whose .684 winning percentage in this stretch is the best in the sport, only have made up 12 games on the Cubs in this time.

The primary reason for the skid is the pitching.

The Mets own the fifth-worst ERA during this stretch with a 5.01 mark, with the starters tallying the seventh-worst figure at 5.08 and the bullpen ranking fifth-worst with a 4.93 tally.

They owned the sport’s best ERA through June 12 with a 2.83 mark, with the starters owning a league-best 2.79 figure and the bullpen posting the second-best ERA at 2.51.

Thankfully for the Mets, their hot start afforded them cushion, and the group of teams trailing them — Giants, Reds and Diamondbacks — are not exactly world beaters.

Fangraphs still gives the Mets an 87.8 percent chance of making the playoffs entering Wednesday, compared to just 7.4 percent from the Giants, 5.4 percent from the Reds and 0.7 percent from the Diamondbacks.