MINNEAPOLIS -- It was a pitch just like any other.
Anthony Swarzak took the sign from Joe Mauer and came to the plate with a first-pitch 91-mph fastball to Mets first baseman Ike Davis with two outs in the seventh inning Aug. 19. But Davis foul-tipped the pitch and it hit Mauer square on the top of his catching helmet with enough force for the ball to go over the backstop at Target Field.
The blow forced Mauer to his knees, causing a short halt to the game, before he stayed behind the plate for the rest of the Twins' 6-1 loss.
No one thought much of the play at the time, but with Mauer feeling concussion-like symptoms the next day during batting practice in Detroit and ultimately being placed on the seven-day disabled list, an otherwise meaningless pitch in a lopsided makeup game could have large implications on the organization.
Mauer is on the comeback trail, taking live batting practice on the field at Target Field this week, and could be activated as early as this weekend against the Blue Jays. But it remains to be seen how much he'll catch the rest of the season and moving forward, as the Twins like him behind the plate, but want to protect their best player.
"We'll just kind of play it by ear," manager Ron Gardenhire said. "I know Joe likes to catch. That's what he's been his whole life. We'll just have to wait and get him back on the field."
Mauer isn't alone, as he's one of eight catchers to be placed on baseball's concussion disabled list this season. It's a disturbing trend, as it only adds to the risks that come with the game's most demanding position.
And when you couple it with the fact that Mauer is undoubtedly the club's best player and the face of the franchise, especially with Justin Morneau having been traded to the Pirates last week, it has the Twins on notice.
"It's a concern for the entire industry when it's increasingly a hazard for that position when your best player is a catcher," assistant general manager Rob Antony said after Mauer was placed on the DL. "Fortunately, he has not had any issues in the past. You hope this is an isolated thing and not a trend for all catchers."
Mauer, when talking to the media last week, confirmed it was his first concussion suffered while catching, but did admit to having one when he was about 12. But the fear lingers that Mauer could sustain another concussion and be out for a longer period of time. That's what happened with Morneau, who suffered several concussions growing up playing hockey before sustaining a career-altering concussion after being kneed in the head while trying to break up a double play in July 2010.
Mauer has taken just about every conceivable precaution -- early this season, he was fitted with a new Rawlings catcher's helmet designed to prevent concussions, and he wears a lightweight titanium mask -- but it clearly wasn't enough to prevent his concussion on Davis' foul tip.
"I hope somebody a lot smarter than me is doing some research on these types of things," Mauer said. "Hopefully we can do that -- get something safer."
But Gardenhire has his doubts that concussions will fully go away with catchers, considering the force at which balls hit the mask and helmet on foul tips.
"The bottom line is if a baseball comes flying out of a guy's hand at 95 mph and gets foul-tipped into your mask, I don't know what you're going to be able to put on somebody's head to keep the head from being jerked back," Gardenhire said. "It's just part of the game. It's going to happen."
With Morneau in Pittsburgh, Mauer will have plenty of chances to play first base the rest of the season, and perhaps beyond, if that's what Minnesota chooses.
But Mauer has always preferred catching, and much of his value comes from the fact that he's among the best-hitting catchers in the game. It also helps that he's regarded as a plus-defender behind the plate, with good pitch-framing skills and a strong arm.
For a positional comparison, Mauer's .880 OPS ranks first among Major League catchers by a sizeable margin, but it ranks fifth among Major League first basemen. Mauer's .476 slugging percentage also ranks fourth among catchers, but eighth among first basemen.
So the Twins will have to weigh the risks that come with keeping Mauer behind the plate to remain an elite catcher with moving him off the position where he'll rank as a very good first baseman, but not elite.
Only time will tell what Minnesota's exact formula will be, but it could simply be less time behind the plate for Mauer like in 2012, when he only caught in 74 of the 147 games he played in while seeing time at first base and designated hitter.
No matter what they ultimately decide, the Twins will have to find a way to keep Mauer on the field, as his eight-year, $184 million deal runs through 2018. The club prefers for him to stick behind the plate, but his health will dictate that.
"We hope to see him catch," general manager Terry Ryan said. "That's his position. You can get hurt on a baseball field no matter where you go. Even DH."
Rhett Bollinger is a reporter for MLB.com. Read his blog, Bollinger Beat, and follow him on Twitter @RhettBollinger.