They were absent so long, it’s sometimes hard to remember they were even a part of the Mets baseball team a year ago. Noah Syndergaard was gone by May 1. Yoenis Cespedes was gone by Sept. 1, but he’d also spent a healthy chunk of summer in civvies, out of sight and out of mind.

It’s worth remembering that.

It’s worth remembering that at this time a year ago, if you were thinking about listing viable candidates for the Most Valuable Player plaque and for the Cy Young Award, the names “Cespedes” and “Syndergaard” would certainly have been among the names you would have pondered.

Then, on April 27, Cespedes strained his left hamstring running out a double at Citi Field against the Braves and missed the next 38 games. Then, on Aug. 25 in Washington, he earned a matched set, straining his right hammy. That cost him the season’s final 35 games.

Three days after Cespedes’ first injury, Syndergaard — who’d been scratched from his scheduled start the day Cespedes went down, who was in the middle of getting cuffed around by Washington for five runs in 1 ¹/₃ innings (in what became an epic 23-5 rout by the Nationals) — threw a pitch at Nationals Park, winced and walked off the mound with a tear in his right lat muscle. He wouldn’t be seen again until 146 days later, and then just for two brief appearances totaling three innings.

Without them — you may have heard — the Mets were dreadful.

Worse, they were dreadfully dull, too.

So as the Mets prepare to officially begin the task of putting 2017 behind them, they will welcome back their two franchise cornerstones, both of whom have vowed they will alter their approaches this time around, both of them seeming to understand, at cost, that their way wasn’t the best way.

Once, they represented a style and a swagger the Mets wanted to promote, hoping the city would embrace this colorful pair as they once had the rakish Mets of the ’80s. Remember spring training two years ago, the two of them arriving at the Mets’ Port St. Lucie headquarters on horseback, the Butch and Sundance of the Grapefruit League?

Remember Cespedes’ fleet of sports cars?

And Syndergaard’s collection of wise-crack tweets?

And, most important, the 2016 seasons that both men put together: Cespedes hitting .280/.354/.530 with 31 homers and 86 RBIs (despite missing 30 games) and Syndergaard going 14-9 with a 2.60 ERA and 219 strikeouts in 183 ²/₃ innings before dominating the Giants for seven shutout innings in the NL wild-card game?

Yo and No.

That is why so much was expected of them last year, and why their absence carved a hole in the team’s very soul. And it is why it is almost necessary to remind yourself: These guys are coming back. And if they can stay healthy — and you can certainly capitalize and bold-face that IF if you’d like — that can only be a profound assist in dragging the Mets where they want — and need — to go.

Nobody is writing their names at the tops of their MVP or Cy Young lists — not now, not yet, not until they can both prove they are back, that they have staying power, that they have honored their oaths to conform to standard training methods and not wander off to their own happy places, both of which were apparently furnished with heavy weights.

It is OK to be skeptical.

Even OK to be cynical.

OK to say, “Show me, please.”

But it is also OK to take a quick look at the back of Cespedes’ baseball card and see that in 270 games as a Met, he has an OPS of .900 (Mike Piazza’s was .915) and an OPS+ of 139 (Piazza’s: 136). It is OK to take a look at the back of Syndergaard’s baseball card and remember he is still only 25, that he still throws hard, that he still has that larger-than-life look and feel to him.

You start there with the Mets, with Yo and No, with Butch and Sundance. If they’re who they used to be, what they were supposed to be? Then you’re looking at a whole different kind of summer at Citi Field. If.