The assumption for quite some time has been that Jorge Alfaro is the Phillies' future at catcher. Nothing has changed in that regard, especially since the burly 24-year-old Colombian joined the Phillies several weeks ago and immediately started showing the hitting prowess the team thought it would see from him earlier this season at triple-A Lehigh Valley.

Some opinions about his big-league readiness defensively, however, are alarming.

"I'm not really an Alfaro guy," a National League scout said recently. "I think he is terrible behind the plate. He's as strong as anybody you'll ever see and he hits the ball as hard as anybody, but I don't know if he's the answer behind the plate."

The pros and cons were on display Thursday night during the Phillies' 4-3 loss to the Nationals down in Washington. Alfaro launched his second home run when he crushed a hanging breaking ball from Tanner Roark in the top of the third inning, but he was charged with a passed ball in the bottom of the sixth and the Nationals were also successful on both of their steal attempts. Bases are often stolen off the pitcher rather than the catcher, but Alfaro's 18 percent success rate (2 of 11) at throwing out runners through Thursday has to get better.

Alfaro's defensive deficiencies are not breaking news, and in a perfect world he would be able to continue working on them for a little bit next season at Lehigh Valley. Alfaro, however, is out of options after this season, so his minor-league development time has expired. If he is going to be in the big leagues next season he is going to be the Phillies' primary catcher, and that could be a delicate situation given the youth and inexperience of the pitching staff.

Jorge Alfaro could provide the Phillies with the kind of elite offense teams rarely get from their catcher. YONG KIM / Staff Photographer
Jorge Alfaro could provide the Phillies with the kind of elite offense teams rarely get from their catcher. YONG KIM / Staff Photographer

Pete Mackanin said recently that  he has not seen enough of Alfaro to draw any conclusions about his defense, but the Phillies manager was emphatic about what kind of catcher he prefers given the choice between an outstanding hitter and a stellar defender.

"Catching is predominantly a defensive position," Mackanin said. "I'd rather have a catcher that doesn't hit, but can run a game, throw runners out, and handle pitchers. Defense is most important, more than hitting. Any kind of offense you get from a catcher is a bonus. If you have a catcher who is a good catcher and a good hitter then you really have something."

You have Yadier Molina, a rare big-league gemstone.

The New York Mets have learned to live with an unpolished Travis d'Arnaud behind the plate even though he has long been considered a defensive liability. His 17 percent success rate (9 of 54) at throwing out runners this season is the second worst among catchers who have started at least 80 games. Only Houston's Brian McCann is worse. McCann has been below league average in that department 10 times in 13 big-league seasons, but he has also hit 20 home runs or more nine times.

The New York Yankees are living with Gary Sanchez's defensive liabilities right now and almost every other team in baseball would too given his ability with the bat. Sanchez is going to hit more than 30 home runs and he has a strong arm, but he leads baseball with 14 passed balls. The Yankees also rank third in the American League with 68 wild pitches, a statistic that is often a reflection of how well a catcher blocks balls. Yankees manager Joe Girardi, a former catcher, has not always liked Sanchez's work behind the plate, but he has mostly lived with it.

The Phillies have seen significant defensive improvement from Cameron Rupp, although his 11 passed balls this season are a career high. They also believe that Andrew Knapp has held his own playing part time in his rookie season.

"Rupp has been OK," Mackanin said. "Rupp has shown improvement calling a game, handling pitchers, and things like that. Knapp I think is leading all rookies [with a .362] on-base percentage. We weren't sure about his catching ability when we broke camp. He has shown improvement. He seems like he is capable."

Alfaro, meanwhile, is raw. He has the strongest arm of the Phillies' catching trio, but he also is the least polished when it comes to catching and calling a game.

"I want a defensive guy, but you better have a very good offensive club if that's the way you're going to go," a National League scout said. "None of the Phillies' catchers are great defensively. You know there are not many catchers who can hit like Sanchez and Mike Piazza, but Alfaro might be one of them."

If he is, then you have to live with his defensive deficiencies for now and hope he gets better later.