"He's pretty impressive," Kratz said. "He's strong. Being the youngest guy, they are normally overly comfortable or extremely overwhelmed. He's neither."
The Phillies envision a major-league future for Joseph. But the team is blessed with catching depth. There is a logjam in the high minors with Joseph, Sebastian Valle, and Cameron Rupp.
Combine that with uncertainty in the majors - Carlos Ruiz, 34, is a free agent at season's end - and catcher becomes one of the more fascinating positions in the organization to watch.
"I don't know what the plan is," Joseph said. "Whatever they have in store for me, I'm excited for it. It's going to be fun."
If history is any indication, Joseph is probably at least two years away from the majors. Only five catchers since 1990 have played at least 100 major-league games before their 23d birthday. All five - Ivan Rodriguez, Jason Kendall, Joe Mauer, Yadier Molina, and Brian McCann - were eventual all-stars.
The Phillies have had just two catchers play in 100 or more games before their 25th birthday. They were Jimmie Wilson in 1925 and Clay Dalrymple in 1961. Both were 24 years old. Lou Marson is the lone Phillies catcher 23 or younger to appear in a game in the last 15 years. He played eight games.
Frandsen looks at Joseph and sees McCann. It is a lofty comparison, although Joseph reached double A when one year younger than McCann. The Braves used McCann as a backup when he was 21. He assumed the starting job at 22.
"They just seem like they are built the same way," Frandsen said. "They are big offensive catchers. They have that presence."
"That presence" is an immeasurable quality but something sought in catchers. Joseph, drafted in the second round by San Francisco in 2009 out of Horizon High School in Scottsdale, Ariz., was not a catcher until he turned 17. The Giants had him spend the last two springs in major-league camp, where Buster Posey could give advice.
Frandsen, a former Giant who still talks to members of that organization, had heard plenty about Joseph before spring training. The reports were glowing.
Last season, Joseph was the fourth-youngest player in the Eastern League. His power output dipped after he made the jump from single A. He produced a .715 OPS with 24 doubles and 11 home runs.
Joseph said consistency is what is most missing from his game. His plate discipline, which yielded a .317 on-base percentage in consecutive seasons, could improve.
"I think I'm a quick learner," Joseph said.
That could be best demonstrated by a 40 percent caught-stealing rate in 2012. His defensive skills have progressed annually, one scout said. That is expected, considering Joseph's lack of experience at the position.
Catching coach Mick Billmeyer said Joseph has come along quicker than he anticipated.
"For 21 years old, he really acts the right way in that clubhouse," Billmeyer said. "I watch how other guys treat him. They have a lot of respect for him."
Or, as Kratz said, maybe it is because Joseph looks nothing like his age.
"That's good," Joseph said. "I like to be a little deceiving."
Contact Matt Gelb at firstname.lastname@example.org.
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