Sunday afternoon, the Washington Redskins let Robert Griffin III play even though he was injured, clearly diminished. In late summer, the Washington Nationals forced Stephen Strasburg to sit even though he was healthy, possibly fine.

The full diagnosis of Griffin’s knee injury remains unknown, but the grotesque bend of his leg in the fourth quarter of Sunday’s playoff loss was enough to presume it is not good. We do not know what will come of Strasburg’s right elbow, but he will arrive at spring training in five weeks with a clean bill of health.

One franchise pillar is questionable. One is unharmed.

The individual circumstances of Griffin and Strasburg differ to the point of perhaps rendering the comparison irrelevant, save for one shared fact. Both decisions drew withering criticism and shined a spotlight on questions that have vexed professional sports teams for years: When is a player too hurt to play? Who should make the decision? How do you maximize players’ gifts while also protecting them?

Recent history offers few clear answers. In 2004, Curt Schilling pitched with the skin of his ankle sutured to a tendon and led the Boston Red Sox to a victory that staved off playoff elimination — and led ultimately to the franchise’s first World Series in 86 years.

Ligaments work to allow the knee to bend forward while limiting its ability to rotate and flex side-to-side. On the play in which Robert Griffin III was hurt, the lower half of his knee makes both of those movements to excess, suggesting an injury to the anterior cruciate ligament.

In 2010, guard Brandon Roy appeared in a playoff game for the Portland TrailBlazers eight days after surgery, helped them to a victory — and was never again the same player.

In 2011, quarterback Jay Cutler stood on the sideline during the second half of the NFC championship game with a sprained knee ligament — and was savaged by many his own peers for not going back in.

When a borderline injury arises, no two circumstances are identical. The stakes of the game, the age and ability (and contract) of the player and the severity of the potential damage all play a factor.

Experts agree on one universal truth, which surfaced Sunday when Griffin, exercising a telling bit of sports vernacular, told Redskins Coach Mike Shanahan that he was “hurt” and not “injured.” Athletes will always choose to play, and should therefore be considered the most unreliable source to answer whether or not they should.

“The emotional need of wanting to play and being a star always overtakes making a good decision,” said Sharon Stoll, a sports ethics professor at the University of Idaho. “You’d like to think an athlete as intelligent as Robert Griffin III would be able to make that decision. But your humanness prevents you from making that decision. That’s why you need a community of medical authorities to step in and say, ‘No, you’re not [playing].’ The athletes themselves, they can’t do it. There’s too much emotional tie-in.”

Schilling experienced that emotion more acutely than most. After he injured his ankle at the outset of the 2004 postseason and then aggravated it early in the American League Championship Series, he assumed his postseason was over. Then physician Bill Morgan “presented the Frankenstein option,” Schilling said — an operation that would come to be known as the Schilling tendon procedure.

“And then it was of course I’m going to pitch,” Schilling said.

The Washington Post’s Mike Jones breaks down the Redskins’ loss against the Seahawks and Robert Griffin III’s injured knee. (The Washington Post)

At 37, Schilling pitched the Red Sox past the New York Yankees as blood drenched his sock in one of the most thrilling postseasons in the sport’s history. Schilling’s career would last three more seasons before it was derailed by a shoulder injury. He was, he said, never the same pitcher after the ankle procedure.

“That was a direct result from trying to come back after the surgery,” Schilling said. “I was probably the worst guy in the world to ask. I’m not trying to be like Braveheart, but I got paid to pitch. I always felt like me at 80 percent was going to be better than anybody else at 100. I think that’s why I was who I was.”

Schilling harbored no regrets. While Griffin, like himself, had gutted through an injury in a playoff game, Schilling drew a clear distinction. He said a player at 37, in the final stages of his career, should be treated differently than a 22-year-old rookie.

“The first thing you always do is look at the window the player is in,” Schilling said. “When I did what I did with my ankle, I was at the tail end of my career. I would have never been able to have a discussion about it the first eight to 10 years of my career. At the end of my career, I had earned the right to decide.”

Adrenaline and competitiveness cloud athletes’ judgment, especially in the intensity of a game. During the second week of the 2001 NFL season, linebacker Mo Lewis slammed New England Patriots quarterback Drew Bledsoe along the sideline late in the fourth quarter. Bledsoe complained of shoulder pain to Thomas Gill, the Patriots’ team physician, but pleaded to go back in the game. For one series, Bledsoe kept playing.

“He’s an incredible competitor,” Gill said in a phone interview. “He’s saying, ‘I’m ready to go.’ He just didn’t look like himself. We brought him inside [the training room] and had a high level of suspicion that something worse was going on.”

Gill, still the team doctor for both the Patriots and Red Sox, discovered he was right. Bledsoe had suffered internal bleeding in his chest and torso, a potentially life-threatening diagnosis. And, again, Bledsoe had to be forced out of the game.

“If you’ve never been in that situation before, it can be easy to succumb to an athlete that says, ‘I’m fine. I’m fine,’ ” Gill said. “It’s not fair to ask a player in the heat of the moment, ‘Do you want to play?’ ”

The difference between being hurt and injured has become cliche, but doctors attach significant meaning to each designation. Players who are hurt, Gill said, can play without the risk of further damage to an injury. Players who are injured can jeopardize their career by playing.

“If an injury has potential for future damage, it doesn’t matter whether it’s a playoff game or the regular season or preseason,” Gill said. “But if it’s an injury where it’ll hurt for a month longer if he plays than if he doesn’t, then the type of game does make a difference.”

Even then, Gill said, “that’s not my decision.” He would explain the risks to the athlete, his agent and perhaps his parents. In that scenario, and only in that scenario, he’ll let the player weigh the pain and choose.

When he shut down Strasburg, Nationals General Manager Mike Rizzo took the choice out of Strasburg’s hands. Rizzo exercised maximum caution with his star pitcher, prioritizing the best odds for a long, healthy career for the player over the best odds for the Nationals to win the 2012 World Series.

“To me, this is a longevity question,” Rizzo said last April. “It’s a health question. It’s caring about the player and the person more so than the won-loss record.”

Rizzo absorbed criticism from former players and from within the sport — one anonymous executive told USA Today he wanted the Nationals to lose in the playoffs because of the choice.

Some may now say the result from Shanahan’s decision to not take Griffin out of the game vindicates Rizzo’s call to shelve Strasburg for September and the playoffs. It is a fair thought, but probably too simple, especially given the differences in the two sports.

Where there is a fair comparison is this: Rizzo did the maximum — some say too much — to protect his player and prized asset, and Shanahan did the minimum — some say not enough — to protect his. And the player who kept playing got hurt.

“Most athletes see themselves as indestructible,” said Stoll, the sports ethics professor. “This isn’t anything new. Athletes do not have a good sense of when they can play, because they can think they can do anything. They believe they’re the best player. They need to be out there.

“To ask a player, ‘Do you think you can play or not?’ All coaches know better.”