Jeurys Familia’s wallet wasn’t the only thing that got heavy last year.

The Mets reliever, after receiving a three-year contract worth $30 million in the offseason, had the worst season of his career and blames weight gain for his dismal results. Now he says he’s lost 30 pounds since the start of the offseason and expects a change in 2020.

“It was a tough season for me,” said Familia, who says he’s dropped from 270 pounds to 240 through workouts with personal trainer Dave Paladino in New Jersey. “I’ve never had a year like that. Gaining weight affected my delivery to the plate and messed up my rhythm, which is why I started … training to take the weight off this offseason.”

As big a flop as Edwin Diaz was for the Mets last season, he didn’t plummet to Familia’s level of disappointment. In his return to the organization after going to Oakland in a trade, Familia went 4-2 with a 5.70 ERA in 66 appearances. By late summer he had been demoted to a mop-up role, leaving a significant hole in the bullpen.

The Mets made a potentially significant addition to the bullpen this offseason by signing Dellin Betances to a one-year contract worth $10.6 million, but haven’t forgotten about Familia.

“Jeurys has been a man on a mission this offseason,” general manager Brodie Van Wagenen said. “He has worked with our health and performance department to improve in every aspect of his preparation. In addition to losing weight, he has spent time with [pitching coach] Jeremy Hefner to better understand his mechanics and his approach. He has been throwing off the mound at Citi Field since before the holidays.”

Familia will have a familiar face leading the charge to jumpstart him: The Mets last week named Luis Rojas as manager, after Carlos Beltran departed the organization following his involvement in the Astros’ sign-stealing scheme. Rojas spent eight seasons managing in the Mets’ minor league system after serving as a coach. Rojas was the Mets’ quality control coach last season.

“I’ve been with the Mets for 13 years and he’s always been there for us,” Familia said. “I think he’s ready. He had success as a manager in the minors and also in the Dominican Republic for four years in a very strong league and has won over there, too. He deserves it.”

Diaz, who was bumped from the closer’s role because of underperformance, was put on a nutrition program at home in Puerto Rico this offseason, Van Wagenen indicated previously. Familia expects the Mets to receive a closer version of the Diaz who was an All-Star selection for the Mariners than the reliever who often appeared lost in 2019.

“I know Edwin, and he did not struggle with the pressure of playing in New York as everyone believes,” Familia said. “I think he just had one of those years, but that’s how baseball works. I see the kind of work he puts in. He’s young and he has the best stuff of any reliever in baseball in my opinion.”

Familia was asked about adding Betances, the former Yankees All-Star, to the mix, along with Diaz returning.

“I think we are going to be a three-headed monster,” Familia said.

The Mets’ best reliever last season was Seth Lugo, who jumped from the setup role to part-time closing duty by necessity. Left-hander Justin Wilson was also a dependable option, and the Mets re-signed veteran Brad Brach after claiming him off waivers. Robert Gsellman is another returning member of that bullpen.

“We have a great team, no doubt we can make it to the World Series if we stay healthy,” Familia said. “We have young guys like Pete Alonso and Jeff McNeil who are coming off great seasons and I believe they are going to be better. We really came together in the second half last year.”