How Phillies will decide when, not if, Alfaro becomes their catcher

It does not seem to be a matter of if Jorge Alfaro will become the Phillies' starting catcher, only when.

So they used the final weeks of the season to get a closer look at the player they believe is their catcher of the future.

In the meantime, there's the question of what the Phillies do at the position until then.

Cameron Rupp will more than likely return next season and Alfaro will start the year in triple A. Manager Pete Mackanin said the coaching staff would like to pair the 28-year-old Rupp with a veteran catcher, not a young catcher like Andrew Knapp, who turns 25 next month and had some growing pains in triple A.

A.J. Ellis, who joined the Phillies in August, could be a candidate to pair with Rupp. He worked well with the young pitching staff and has expressed a willingness to return. He also could be vital to helping Rupp improve his defense and game management.

"If you have two young catchers, I don't think that is the best way to go about it," Mackanin said. "I think it's important to have a catcher, like an Ellis or Chooch, who has a good proven idea to lead them in the right direction."

Rupp batted .252 this season with 16 homers and 54 RBIs. His .447 slugging percentage ranked third among National League catchers who played at least 100 games. His offensive production is serviceable, but his defense brings concern. Rupp threw out just 27 percent of baserunners trying to steal, a mark that dropped from 38 percent in 2015.

"His caught-stealing percentage is not the greatest," Mackanin said. "He's got some areas he needs to improve on offensively, and if he does that he could be a No. 1 catcher. That's a defensive position foremost. You need a solid defender back there who can call a game and throw out runners. He's made strides in that area, but he needs more work."

It would be a surprise to see both Alfaro and Knapp begin the season as catchers on the same minor-league team. A time-share at triple A would do little good for two players who need time to grow behind the plate. Knapp played some first base last year in spring training but did not start a game there in the minors. That could be a possibility. He also could be a candidate to be traded this winter.

The catching job at Lehigh Valley will likely belong to Alfaro, who was named the minor leagues' top catcher this season by Baseball America. The 23-year-old has an incredibly strong arm and he worked throughout the summer on his defense and receiving with Dusty Wathan, who managed double-A Reading but is moving next season to triple-A Lehigh Valley and will again have Alfaro as a pupil.

"He was behind the eight ball a little bit. So just catching consistently helped," Wathan said. "Plus, I think the other thing was learning to just catch pitches and not worry about doing too much with pitches. Eventually that will come and you'll get better with receiving and presenting the ball to the umpire."

Alfaro threw out 44 percent of 75 would-be base stealers this season at double A. The biggest concern is his defense, as Alfaro was charged with seven passed balls, including a key gaffe in the Eastern League playoffs. But that, the Phillies believe, will improve with more playing time. Alfaro had caught just 51 double-A games before this season. He battled injuries when he was with the Texas Rangers. Alfaro is far from a finished product.

"I've been working hard on my defense," Alfaro said. "It feels like the hard work has paid off. It's not enough for me right now. I want to keep working and keep getting better. Make myself the best player that I can be. Everything got better. I had some trouble blocking, receiving, and even throwing sometimes. But I worked hard all season long and everything is coming together. I'm not going to stop. I'm going to keep working."

Alfaro spent the final month in the majors because he was already on the team's 40-man roster. He worked on the field before each game with Wathan and Phillies catching coach John McLaren. It was a chance for Alfaro to get a taste of the big leagues. He will return to the minors in April, but then it should just be a matter of time until he is back.

"He's going to work," Wathan said. "He's one of the hardest workers that we have. He's a competitor and he wants to get better at everything he does. A lot of it is a tribute to his hard work."

mbreen@phillynews.com

@matt_breen philly.com/philliesblog