Glover Teixeira didn’t need the UFC light heavyweight championship to be happy. The way he tells it, life over his first four decades turned out pretty great, with family and friends, a successful fight career and a gym of his own in Danbury, Conn.

But that gold he won last October, two days after turning 42 years old, serves as validation for everything he worked toward over 20 years as a professional fighter.

“I was happy before the belt; I even said that many times,” Teixeira recently told The Post over the phone. “I say that the belt is the cherry on the cake, man. It’s gonna summarize my whole career, my hard work.”

Now comes the next chapter — assuredly one of the last in a decorated career — as Teixiera (33-7, 28 finishes) puts his gold on the line for the first time Saturday in Kallang, Singapore in the UFC 275 pay-per-view (10 p.m. ET) headliner against Jiri Prochazka.

Prochazka (28-3-1, 27 finishes), 29, wasted little time earning the fight against Teixeira. Two tour de force victories in his first two years over top 205ers Volkan Oezdemir and former two-time title challenger Dominick Reyes did the trick. It’s rare in today’s MMA landscape for a UFC newcomer to rise so fast, but that’s because the Czech challenger already built an impressive résumé before his arrival, something his coaches urged.

The same thing happened along Teixeira’s journey, as he arrived in 2012 as a respected veteran with a 17-2 mark, victories over several UFC veterans and the cachet of being a primary training partner of mid-aughts superstar Chuck Liddell. But while Prochazka says his patient approach was a strategic decision by his team, Teixeira’s delayed UFC debut resulted from visa issues stemming from the way he initially arrived in the United States as a teen, a harrowing tale he recounted last year.

Nonetheless, Teixeira sees value in the way both he and his opponent didn’t rush to the biggest stage of the sport. He suggests “waiting is just preparing you for the glory,” a message he passes on to the fighters at Teixeira MMA & Fitness.

“I have a lot of students right now, a lot of young guys [and] amateur fighters, and I keep telling them, ‘Don’t be [in a] rush. Don’t try to rush to get to UFC,” Teixeira said. “Because I always thought, it doesn’t matter how long it takes to get there, it’s how, am I prepared to stay there.

“A lot of guys, after four or five fights, they get in UFC [after] maybe only a few years [of] training, some of them do well and keep going, but some of them when they face the level that the UFC has, especially if you’re getting it that early, it’s very tough because the level is so close, the guys are so tough, so strong, and you’ve gotta be at the top of your game.”

It took Teixeira just shy of 10 years to get to the UFC. His 10-year anniversary with the promotion just passed at the end of last month. Tuesday marked the 20th anniversary of his MMA debut — a loss at one of the earliest events from former well-regarded organization WEC. 

Staying power such as that from fighters at the heavier weight classes is not uncommon. But Teixeira’s championship victory over Jan Blachowicz was more than merely uncommon as he became the oldest fighter in UFC history to win his first title. Few could have imagined such a feat even three years ago. And the champ “never imagined” he would be competing 20 years after turning pro, let alone at the top of the mountain.

“I didn’t have imagination back then,” said Teixeira, considering his mindset as a young man just beginning in a young sport. “I was just thinking I’d be retired by 35, back then. Then, when I got to UFC, I’d say, “Maybe if I fight ’till I’m 40, I’d be a very happy man. And here I am, 42 with the belt, so this is incredible.”