The rarely told story of the 1977 Broncos begins in a hospital bed.

Craig Morton’s left leg looked like it had been run over by a pickup truck.

“It was completely black,” Morton was telling me on Friday. “Full of blood. I could not stand up.”

When the 1977 Broncos are honored Sunday as the first Broncos team to reach the playoffs and a Super Bowl, consider Morton’s sacrifice in the AFC championship game on Jan. 1, 1978.

Consider the pain. And consider why he played anyway.

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What the world didn’t know about the Broncos quarterback that week is that he had not stood on his own two feet from Monday through Saturday. The Raiders, the opponent, didn’t know. The media didn’t know. Broncos coach Red Miller had closed practice all week. Miller was asked each day how Morton looked. Miller responded each day, “He looked pretty good.”

Morton was across town in a hospital bed. As Morton, a member of the Broncos Ring of Fame, tells the story, he had sustained a “devastating” hip pointer prior to a Week 14 game at Dallas.

“We were going to Dallas and Red said, ‘What do you think?’” Morton recalls. “I said, ‘Red, I think I’ve been in the hospital to see if they could drain the blood out. I don’t think I can play. I didn’t want to let this thing explode again.’

“So, I played the first series. (Cowboys defensive back) Charlie Waters blitzed me and it exploded again. Hurt like hell.”

Before there was John Elway or Peyton Manning, there was Craig Morton. The forever-feisty 81-year-old will be at Mile High on Sunday, a driving force of a Broncos team that changed the Front Range and of the reunion itself.

“We’ve tried to get this ’77 reunion for so long,” he says. “I guess somebody finally listened.”

The Broncos had gone 12-2, a franchise record for wins after never winning more than nine in 17 pro seasons. In the playoffs they beat the Steelers and Raiders, the opponent this Sunday.

They were safety Steve Foley, whose 44 interceptions remain an unbreakable team record and who will enter the Ring of Fame Sunday.

“Steve made all the right plays at the right time. He had great anticipation, instincts. He studied the game relentlessly,” Morton says. “And he’d hit you. He’d knock your (expletive) off.”

They were tight end Riley Odoms, who began his career playing 112 straight games, holds the team record with seven straight games with a touchdown pass and twice was named All-Pro.

“Up until his retirement, Riley was the best tight end who had ever played,” Morton says.

They were Randy Gradishar, Louis Wright, Billy Thompson, the Orange Crush defense.

“I’m sure there are defenses that people say were better,” Morton says. “But I’ll compare any defense that ever plays to the Orange Crush defense.”

And the week of the AFC championship game they were without the starting quarterback — Morton, who had finished second in MVP voting and was the Sporting News Player of the Year.

Red Miller had gone to the hospital Wednesday to share the game plan with Morton. It was Morton’s only connection to the team during championship week. He couldn’t put pants on.

“They’d stick needles in me every couple hours. My left leg, it was thick. They couldn’t get the blood out,” Morton said. “There was no way I was playing. I couldn’t get out of bed.”

Loren Hawley, his best friend and teammate at Cal, visited the hospital Sunday morning.

“He said, ‘You’ve worked too hard for this. We’re going to the stadium,’” Morton says.

They pulled up to Mile High 3 hours before kickoff. The wind chill in Denver was 4 degrees above zero, “not exactly good weather for my condition,” he says. Morton sat in the whirlpool to “loosen up the blood” as Broncos strolled past to see their quarterback for the first time in a week.

“Pretty sure they didn’t like what they saw,” he says.

The final test was getting his cleats on. Morton told Miller, the coach: You tie my shoestrings and I’ll play. Red “got down on the carpet and we took the field,” Morton says.

On their first series, Morton hit Haven Moses on a 35-yard pass that Moses turned into a 74-yard touchdown.

“I said to my (offensive) line: If they don’t hit me, we will win,” Morton says. “I only got hit twice and both (times) I fell on my right side. If I fell on my left side, it would’ve exploded again.

“I’d still be crying on the field.”

The Broncos beat the Raiders, 20-17, to advance to Super Bowl XII. Denver hiding Morton’s injury led to the NFL changing its injury-reporting policy. They were rule-setters and trailblazers.

“After the game, I went in the shower and hadn’t cried like that since I was a little boy,” he says.

Why did Morton play the hated Raiders after a week in which he couldn’t walk on his own?

You.

“The truth of the story is that 1977 Broncos team played for the Broncos fans. Every single game in that city was magical,” Morton says. “Broncos fans were the best. I don’t care what fan you are. You’re not better than Broncos fans. Any place in town you’d go, they’d be so respectful and say hi and stand up and clap. It was magic. It was the best season of our lives.”