PHOENIX -- Sebastian Rivero was standing in line at a Panda Express in November when he got a call from Royals assistant general manager J.J. Picollo.

It was the news Rivero had been waiting for all year -- and, really, since he signed with the Royals as a 17-year-old catcher out of Venezuela in 2015. He was being added to the Royals’ 40-man roster.

Rivero had a suspicion that he would get the good news earlier in the day when Picollo texted him asking if he could call. Rivero called his wife immediately to give her a heads up, and he said that she always expected it to happen. And when he got the official word from Picollo, Rivero called his parents in Venezuela.

“They [brought] me to tears, because they are not here,” Rivero said Wednesday. “They want to share that kind of stuff with you.”

The Royals added Rivero to their 40-man this offseason to protect him from the Rule 5 Draft after the significant strides they saw him make at the alternate training site last summer. Rivero has always been lauded for his defense and natural leadership skills that come with the position, but his bat hasn’t given him future everyday upside as a Major League catcher.

That might have changed this year.

“I’ll make a bold statement,” said Royals manager Mike Matheny, who caught in the Majors for 13 seasons. “Behind the plate, he’s ready to catch. He does everything you want to see as far as game management, as far as communication, as far as taking charge, as far as receiving, blocking, throwing. He checks all those boxes, and we’re also watching growth, physically.

“He developed his swing completely, almost from the ground up. We’ll see him a little more upright, where he’s able to generate more bat speed and power. And just the kind of guy who has so many of the intangibles behind the plate with how he handles himself back there. Even for a young guy, he has a presence behind the plate and a leadership kind of mentality.”

Rivero, 22, played most of 2019 in Class A Advanced. He stayed in Arizona over the winter and worked out with the Royals’ strength and conditioning coaches, adding strength that has fixed some of the deficiencies seen in his swing before. Then at the alternate training site in 2020, Rivero worked with hitting coaches on his swing mechanics, including his contact point and his footwork. Once he made that adjustment, the pieces began falling into place. He saw more pull-side power, more hard-hit rates and more consistency than he’s ever seen.

“I want to do too much with the swing and everything, try to hit the ball 600 feet, and that’s not going to happen,” Rivero said with a smile. “I got a little narrower in my stance. My bat path was working great to the ball. They were on me every day, ‘Don’t lose that, don’t lose that. Calm down.’”

It’s led to an uptick in confidence that his offense can now match his defense. On Wednesday, Rivero got his first Cactus League start and ripped a double and home run while having an excellent day behind the plate.

“He meant business from the first pitch,” starter Brad Keller said. “He was out there sticking balls, getting me calls that were just off on both sides, inner half and outer half. We talked in between innings about what we wanted to do, how we wanted to attack guys. He was out there reading swings and seeing stuff I wasn’t able to see.”

Catchers are often the busiest players in Spring Training, between catching bullpens, live batting practices and games, as well as getting in their own work. They have their own schedule on top of the daily camp schedule, and Rivero has been able to shadow five-time Gold Glove winner Salvador Perez, also a native of Venezuela, through it all. Perez is entrenched as the Royals backstop this year, and his backup is likely Cam Gallagher or Meibrys Viloria. Rivero still needs to see his improved swing translate into Minor League games, but he’s worth keeping an eye on this season.

“He’s a good kid,” said Perez, 30. “He always has questions that I’m trying to answer, and he likes to play. He likes to compete and is always ready. He’s got energy, kind of like me. I have high energy, but not like him at 22 years old. I don’t know, but I think he’s close to getting to the big leagues.”

Matheny calls what he sees happening on the backfields a “master course in catching.”

Rivero just tries to soak it all in.

“It means a lot,” Rivero said. “Salvy is, for me, the best catcher in the Major Leagues. Others would tell you he’s not. For me, he’s a great guy, a great teammate. I don’t think he knows that he’s my favorite player still, but everything that Salvy does out on the field, I write it down in a book, like this might help me down the road and everything.”