With all the fanfare laid upon the Mets’ bullpen through the early going, Paul Sewald has been something of a forgotten man.

Jeurys Familia has regained dominant form as the closer. Robert Gsellman and Seth Lugo have been revelations as they have made the transition from starters to relievers. Neither setup man AJ Ramos nor lefty specialist Jerry Blevins had given up a run through their first seven appearances. Hansel Robles struck out 10 of the first 15 batters he faced since his return from Triple-A following a brutal spring. Even Jacob Rhame picked up a save against the Nationals before he was sent back to the minors.

And Sewald? He pitched two innings in the third game of the year, and nine days later, reappeared to throw two pitches.

Sewald made a full return from witness protection program Saturday, throwing three perfect innings with five strikeouts as the Mets fell to the Brewers 5-1 at Citi Field.

“It felt really good to get out there and throw some innings,” Sewald said. “I know it’s tough, we were down, [but] it was good to eat three innings so that a lot of our bullpen guys that are tired can kind of take the night off so we’re ready [Sunday].”

The 27-year-old righty relieved Matt Harvey to start the sixth inning and struck out the side. He retired the side in the seventh by inducing weak contact and then picked up two more punchouts in the eighth. He breezed through the lineup on 48 pitches.

“There weren’t any mop-up innings — when you win nine straight, there’s no chances,” said Sewald, who has been throwing on the side to keep himself fresh in between appearances. “I’ll pitch once every 10 games if we’re going to go 9-1, that’s fine with me.”

Sewald’s re-establishing himself as a viable threat out of the bullpen provides an important piece for manager Mickey Callaway, who before the game cautioned he was keeping tabs on his relievers’ heavy usage early on.

Through 13 games, the Mets bullpen has now thrown 46 ¹/₃ innings compared with the starters’ 64 ²/₃.

“That was huge, that saved us,” Callaway said of Sewald’s outing. “We’re going to have games like this where somebody’s going to have to eat up some innings and he did a great job. He went out there and attacked, he mixed his pitches well, and he’s got a lot of deception.”