People in sports who have sexual orientations that are different from the majority have traditionally been inclined to keep their private lives, private. And like the military, athletes and those that cover them have tended to follow a "don't ask, don't tell" policy.
Going public about one's sexuality is never a completely smooth journey, suggests former NBA player John Amaechi.
In February, with the publication of his book "Man in the Middle" (ESPN Books), Amaechi became the the first professional basketball player to openly admit his homosexuality.
"This man is truly brave," Amaechi said of Penner. "Your average jock will initially have a hard time viewing him as a woman."
"People don't understand homosexuality or bisexuality, and transsexualism is a taboo in some respects, even within the gay community," suggested Amaechi, who is now a psychologist.
Still, the former Penn State hoops star predicts the response of athletes is likely to be no different than the general population from which they come.
"You will have some who are miserably against it. You will have the people who are very supportive and some who are part ambivalent and part confused," said Amaechi.
"I think it is going to take some real adjustment on the part of other sportswriters in the Los Angeles Times newsroom, other people in the sports media here in Los Angeles, athletes that she comes in contact with," said Steve Mason, sports talk show host for 710-AM radio (ESPN) in Los Angeles.
But Mason, who praised the "heartfelt" column, also said it's hard not to root for Christine Daniels.
"You feel for this person and what they have gone through," said Mason. "But I am one who believes people are far more enlightened, even in the world of sports, than people give all of us credit for, and I think she will be just fine."
Howard Bragman, head of the Los Angeles public relations firm Fifteen Minutes, applauded the forthright approach taken by Mike Penner.
"This is a courageous act. He's putting a face to something that is not really talked about, " said Bragman, whose firm represents several high-profile gay athletes, including Amaechi, former WNBA all-star Sheryl Swoops and golfer Rosie Jones.
"By writing the column and controlling the first information that is out there, you really get to set the agenda for how to discuss it," Bragman said.
Characterizing herself as a "transitioning transsexual," Daniels told the Times she began dressing full time as Christine four months ago, when she began taking hormones.
Concerned for her privacy, Daniels said that it's "too early" to reveal whether she intends to have surgery to complete the physical change from male to female.
Mike Penner was married to a fellow sportswriter at the Times, and there are unconfirmed reports that the pair have separated.
After 23 years with the Los Angeles Times, Christine Daniels' future there may be changing as well. After a few weeks of vacation, she plans to return to the paper.
In addition to a sports blog, latimes.com reportedly plans to offer her space to chronicle this watershed period of her life and gender transformation.
The tentative title for the column: "Woman in Progress."