There was a time when Jens Pulver couldn’t stand B.J. Penn. There was also a time when he was a little bit scared of him.

But when Penn took to the cage against Frankie Edgar for what he later insisted was the last fight of his career, Pulver was in the crowd watching, wearing a B.J. Penn T-shirt and cheering on the man who had once been his fiercest rival. It felt good to be there supporting Penn, he said, “because we buried that hatchet years ago.”

What he saw once the fight started, however, that hurt even from Pulver’s seat in the crowd. It was also a familiar sort of pain for Pulver, who says he’s also finally retired for good at the age of 38.

“What got to me watching that was, I understood,” Pulver told MMAjunkie. “It’s the hardest thing to realize when you’re in there, because in your mind you’re like, ‘I can do this.’ But once you’re in the fight, it’s like you’re not doing anything. That was the hardest part for me to watch. I was looking at him in that fight and going, ‘I get this. I know that feeling.’ Nobody told us how to get old. Nobody told us what getting old was supposed to feel like. There’s no magic switch where it all shuts off.”

Pulver took his own path to that realization. His last fight in the UFC was a second-round submission loss in his rematch with Penn at The Ultimate Fighter 5 Finale in 2007. After that came a tortured run in the WEC, where he went 1-5, including a brutal drubbing at the hands of then-WEC featherweight champion Urijah Faber – a bout in which Pulver proved a brand of toughness that had never really been in doubt simply by lasting the full five rounds.

After bouncing out of the WEC in 2010, however, Pulver spent the next few years going up and down on the regional circuit before coming up short in the ONE FC bantamweight grand prix. He made a couple unsuccessful stabs at calling it quits along the way. He kept trying to be done with MMA, then changing his mind.

Maybe that’s why he empathized with Penn, who came back to take one more beating that seemed pointless and unnecessary to everyone but him.

“I know what he’s going through in his mind,” Pulver said. “After all the battles, he’s going, ‘Man, one more time. Let me grab somebody and knock them unconscious. Let me submit one of these kids.’ And it just doesn’t happen come fight time. I’ve been there.”

Pulver began his MMA career in 1999, back when there didn’t seem to be much of a future in it, especially for guys his size.

“When I chose to do this sport, they didn’t even have the (155-pound) weight class,” Pulver said. “Who in their right mind would chose to do this when they don’t even have a place for guys your size?”

He would go on to become the UFC’s first lightweight champion, bouncing from the UFC to PRIDE to the IFL and the WEC, and just about everywhere in between. When he sees people questioning greats from his era, such as Penn, he still feels that sting.

“Because I know they’ll ask that about me,” Pulver said. “But don’t overlook what we did, when we did it.”

Just as MMA needed the Pulvers and Penns to go from that age of the sport to this one, he noted, it also needs them now. As they slide into retirement, they’re teaching the fighters of this era a lesson that they never had the chance to learn. They are showing them how to get old. They’re teaching them how to recognize the end, and maybe even how to deal with it.

“I wish there was some kind of book, the ‘getting old’ book,” Pulver said. “I wish there was a playbook for it. Because you’re sitting there thinking, ‘Why can’t I do what I did?’ You’re looking at this road in front of you, and suddenly it’s dark. Athletically, it’s over. It’s done. What are you supposed to do? It’s getting easier. I’m trying to replace it with other things. I have my family, my kids. I’m doing coaching, these other things I always wanted to do. I got over the scary hump of the idea. And now, watching B.J. facing it, it’s just … it’s time.”

As for what his future holds now that fighting is no longer an option, Pulver isn’t totally sure. He enjoys coaching, and he enjoyed his time as a color commentator for the WEC. He was good at it, too. It helped to remind him that there was more to him than what he could do with his fists, that his life wasn’t over just because one part of it was.

“When I wanted to be a world champion, I became one,” Pulver said. “Now I’m trying to figure out what I want to do next, and when I figure it out, I’m going to become a world champion again.”

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