Golf isn’t about the passage of time. It’s about the passage of eras. Sometimes the signs are subtle. Sometimes they’re unmistakable.

Jordan Spieth’s victory at The Masters was much more than his first major championship, much more than the 21-year-old Dallas native’s assault on the Augusta National record book. It marked the end of the era defined by Tiger Woods and the beginning of the era defined by those young players he influenced.

“An exciting new era has just arrived,” CBS Sports broadcaster Jim Nantz told viewers after Spieth polished off a dominating 270 (18-under par) to win his first green jacket. “The next generation is officially here.”

Eras in golf are defined by a duo, or sometimes a trio, of tremendous players who elevate the game to heights unseen to that point. That’s how you trace the game’s history and how it transitions from one era to another.

Ben Hogan, Byron Nelson and Sam Snead dominated the 1940s and ’50s. Arnold Palmer and Jack Nicklaus defined the 1960s. Nicklaus transitioned to the 1970s and locked horns with Tom Watson well into the early 1980s.

From there the game floated like a directionless buoy, with no dominant voice, until Tiger Woods grabbed the game by the throat at Augusta in 1997 and launched a new era.

Woods dominated that era, but Phil Mickelson was his closest rival. Until Woods’ fall from grace several years ago they defined perhaps the game’s most popular stretch. Woods redefined who could be a golfer; he created casual fans and launched golf’s rise as a billion-dollar sport.

Woods did it with a laser-like focus, a “golf-is-my-life” attitude and a rise to greatness that seemed preordained. Meanwhile, Mickelson’s easygoing personality and his go-for-broke playing style — and the disappointment it sometimes created on golf’s biggest stage — humanized him to fans and helped him create his own latter-day “Arnie’s Army.”

Fans deeply respected Woods’ game, but not everyone connected with him. He, at times, seemed otherworldly. Fans found Mickelson’s success and his attitude down-to-earth, which made him much easier to like.

So where will Spieth fall on the Woods-Mickelson continuum?

Spieth feels more like a Mickelson than a Woods, though to be sure Woods had heavy influence on Spieth’s game, which has been on display locally since his days as a teenager playing in the Byron Nelson on a special exemption.

Chuck Cox, who covered Spieth in high school while working for People Newspapers, said he noticed right away that Spieth approached things differently than Woods.

“He has the right attitude,” Cox says. “I think with Tiger it was so ingrained in him; from the word go it was an obsession with him and his dad [to be great]. Jordan doesn’t have that. He liked golf from an early age, and his parents were not overbearing about it.”

Spieth admitted the final round was “nervewracking,” but he never quite let it show, only allowing his emotions to rise to the surface a couple of times. He looked comfortable, even if he wasn’t so much.

Like Mickelson, he’s the product of a family with siblings (Woods is an only child), and Spieth found himself locked in all sorts of competitions with his brother, Steven, now a starting guard at Brown University.

His younger sister, Ellie, has special needs. Spieth calls her “his hero” and the reason he remains so grounded. When Nantz asked Spieth earlier in the week about his humility, Spieth countered with this: “Me talking about humility is difficult because that wouldn’t be humility.”

Spieth led this tournament wire-to-wire, but each night he stayed in at an Augusta home with his family, playing cards with his grandfather, Bob. There was one house rule — if Spieth walked into the room and golf was on the TV, the TV had to be turned off.

Golf is his sport, but he doesn’t seem to let it define him quite the way Woods did. Spieth is still dating his high school sweetheart from his days at Jesuit. His parents, Chris and Shawn, were high school sweethearts too.

He walked off the 18th hole on Sunday arm and arm with his parents. When he reached the clubhouse to turn in his scorecard, he found several caddies waiting around to congratulate him, including Mickelson’s own caddy, Jim “Bones” Mackay. Former Masters champion Zack Johnson was there as well. Bubba Watson, the defending champion, congratulated Spieth’s parents before the final putt fell.

If it all felt like a love-fest, well, it kind of was. In fact, it was a love-fest most of the afternoon. “He’s hard not to like and not to pull for,” Mickelson said.

“This is a new man who could carry our game on for decades,” three-time Masters champion Nick Faldo told viewers. “He isn’t intimidating, but he sure is demoralizing [to opponents].”

Now, along with everything else, Spieth is the No. 2 ranked player in the world. Who’s No. 1, you ask? Rory McIlroy, another of Woods’ young disciples. Like Woods, McIlroy is an only child who took to golf incredibly young and projected prodigy-like skills.

So here we are, in golf’s new era. We have our new players, and for the first time since the 1950s, it will be a player from Dallas-Fort Worth who will define golf’s new direction.