Joe Mauer literally went through a growth spurt after winning his first batting title in 2006, climbing from 6-4 to 6-5 at age 23.
In a lighthearted moment the following spring, Mauer acknowledged that he's actually 6-6 "wearing shoes."
"I don't want to get too big," Mauer said, "or I might have to move [positions]."
The growth spurt stopped, but at 6-5, Mauer is as tall as any catcher in baseball history. Questions about his future at the position keep returning, especially now that he's back on the disabled list with what the Twins have called "bilateral leg weakness."
Mauer has won three Gold Glove Awards and three batting titles, but he's also had two surgeries on his left knee, including one in December. He missed the first month of his 2009 MVP season because of a lower-back injury that doctors continue to monitor.
Mauer, who turned 28 on Tuesday, is making $23 million in the first season of an eight-year contract, so his playing position is a potential franchise- altering issue for the Twins, yet it pains them to talk about it publicly.
Asked this week whether Mauer's height adds to concerns about his durability at catcher, Twins General Manager Bill Smith simply said, "No." Smith noted that another tall player, Carlton Fisk, caught more games than anybody in major league history before the 5-9 Ivan Rodriguez broke the record.
Various listings had Fisk at 6-2 or 6-3 and about 200 to 220 pounds. The 2011 Twins media guide lists Mauer at 233 pounds, making him both bigger and heavier than Fisk, Lance Parrish, Mike Piazza or any of baseball's top 25 leaders in games caught since 1919, according to Baseball-Reference.com.
Other notable major league catchers listed at 6-5 include Baltimore's Matt Wieters and former Cleveland All-Star Sandy Alomar Jr. But according to Baseball Prospectus research, no catcher listed at 6-6 or taller has accumulated more than 200 at-bats in the majors.
For Mauer, being tall is one thing. Being tall with chronic knee and back issues is another.
Dr. Aimee Klapach, an orthopedic surgeon at Sports and Orthopedic Specialists in Minneapolis, said a person's size has a direct relationship to the stress that's put on joints, such as knees and ankles. And in Mauer's case, his weight -- even though he is in good shape --might be a bigger factor to stressing his joints than his height.
"Every extra pound adds an extra three to five pounds to what a lower extremity joint feels," she said. "If a person is carrying 15 extra pounds, that's 45 pounds or more of what the joint feels. ... The bigger you are, the more load you're going to see across the joint, especially for a position like catcher, where it's up and down, and you're sort of in an awkward position for an extended period of time. That joint is going to see an increased load compared to someone who's shorter or lighter."
Klapach said that for a large person with healthy knees, it's difficult to predict problems. But for a person who already has had knee surgery and is missing some cartilage, like Mauer, deterioration of the joint at some point is a given.
How long a repaired knee can withstand the stress of an activity like catching is the unknown in Mauer's case. But the likelihood that it will affect him is a virtual certainty.
"We just don't know the rate of deterioration," she said. "In some patients, it happens very quickly."
Since making his major league debut in 2004, Mauer has caught in 728 games. Over that same span, A.J. Pierzynski has caught in 911.
The 6-3, 225-pound Pierzynski, now with the White Sox, is the player the Twins displaced to make room for Mauer before his rookie season.
"The thing is, sometimes it's luck, and freak things happen to you," Pierzynski said. "Joe was unfortunate early in his career to have knee problems. I know they've been talking about moving Joe [to another position] for years. But he's much more valuable as a catcher than any other position because he's pretty darn good back there."
Fisk is among the Hall of Fame catchers who had to play other positions. He injured his knee in a home-plate collision in 1974, his third full season, and went on to DH for 42 games in 1979. He also started 27 career games in left field and nine at first base.
Yogi Berra spent time in the outfield to help the Yankees make room for catcher Elston Howard. Johnny Bench finished his career with 111 starts at third base, 70 at first base and another 45 in the outfield.
Mauer, who starred at quarterback and point guard at Cretin-Derham Hall, has repeatedly said he hopes to continue catching as long as possible. During spring training, when he was limited to eight games and 20 official at-bats, he said his main focus was on rebuilding leg strength.
This is paramount for catchers. Rick Dempsey, who ranks 18th on baseball's career list with 1,633 games caught, said he made running a daily ritual, even in the offseason.
"I never, ever let my legs get out of shape," Dempsey said. "It was a 365-day-a-year job for me. That's why I lasted so long."
Dempsey, now an Orioles analyst for the Mid-Atlantic Sports Network, had more of a prototypical build for a catcher at 6 feet tall, 190 pounds. This year, the average major league catcher stands 6 feet, 0.5 inches tall and weighs 216.8 pounds.
Wieters, the Orioles' starting catcher, is listed at 6-5 and 225. He's already gained an appreciation for the physical demands of the job.
"I'll lose anywhere from 10 to 20 pounds [during the season]," Wieters said. "I'll come into the season around 235, and I'll try to finish the season around 220, 225. Last year, I ended up around 215 so I lost around five pounds more than I wanted."
One month shy of his 25th birthday, Wieters has caught in 226 games.
"He's not big and heavy; he's lean and wiry," Dempsey said of Wieters. "That might work in his favor."
The durability questions are there for tall catchers, even when they're healthy. Besides the leg weakness, Mauer is trying to get over a virus that put him in the hospital and made him lose 12 pounds.
"Right now, [Mauer's height is] not a concern for me," former Twins catcher Tim Laudner said. "Let's get him healthy, put some weight back on him and then we'll see where we're at."
Star Tribune staff writers Dennis Brackin and La Velle E. Neal III contributed to this report.