LAS VEGAS -- Los Angeles Angels general manager Billy Eppler made his mark as a front-office executive while helping the New York Yankees navigate through one of the biggest transition periods in franchise history.

The four-year stretch from 2013 to 2016 coincided with the retirement of Derek Jeter, Mariano Rivera, Andy Pettitte, Alex Rodriguez and Mark Teixeira. It saw the Yankees spend nearly $600 million on six high-profile free agents -- Masahiro Tanaka, Aroldis Chapman, Brian McCann, Andrew Miller, Jacoby Ellsbury and Carlos Beltran -- but also splurge so aggressively in Latin America that the rules eventually changed. Editor's Picks The many ways Mike Trout dominated in 2018

Winter meetings predictions: Will Vegas deliver any last-day drama?

MLB offseason: Complete coverage of free agency and more 2 Related

It was a form of what is called "rebuilding on the fly," though the Yankees, true to their nature, executed it on a grander scale.

Eppler -- a key assistant to Yankees GM Brian Cashman for the first three of those years -- is on the cusp of a similar, albeit more subtle, transition with the Angels, bucking the trend of an industry that is increasingly operating on both ends of the spectrum.

The Angels aren't "all in," because they won't surpass the luxury-tax threshold and won't trade quality prospects for short-term fixes. But they aren't "rebuilding," because they're still doing whatever they can -- within whatever they consider reasonable -- to win in 2019. It's a product of employing Mike Trout, the greatest player of his generation, for at least two more seasons; of being saddled with what remains ($87 million) on Albert Pujols' contract; and of being run by an owner, Arte Moreno, who has no interest in pushing the proverbial reset button.

Eppler defined the approach this way: "What you're trying to do is give yourself an opportunity to continue to win every year, and if everything kind of falls right from a projection standpoint, you might push yourself even into the postseason. You might be there. It's within your band of outcomes. That's how I determine 'rebuild on the fly.' But you're going to make some short-term decisions. And you're most likely not going to trade things that have multiple, multiple years of control. Maybe one more year of control, things like that. But you always have to kind of keep yourself in a competitive window to still have, within your band of outcomes, an 86-or-better-win team."

Since their run of five division titles from 2004 to 2009, the Angels have won as many as 98 games (2014) and as few as 74 (2016). But the other seven seasons finished somewhere between 78 and 89 wins -- good enough to have a chance, bad enough to fade.

The Angels operated aggressively from 2012 to 2014, a stretch that saw them acquire Pujols, Josh Hamilton, C.J. Wilson, Zack Greinke and Huston Street. Since then, they have lived in that awkward middle space widely considered baseball purgatory, going cheap on free agents and staying conservative in the trade market.

In some weird way, it might actually be working. The Angels' farm system ranked 30th -- dead last -- as recently as 2017 and jumped all the way to 10th in August 2018, according to Baseball America's organizational talent rankings. Jo Adell, Jahmai Jones, Brandon Marsh, Griffin Canning and Matt Thaiss -- all drafted between 2015 and 2017 -- performed well as they matriculated through the system. So did Luis Rengifo, acquired from the Tampa Bay Rays for C.J. Cron in February. With three international signing periods, Eppler also restocked the lower levels.

"I can see the growth," Eppler said. "I know people outside can see the growth. I've had opposing general managers tell me, 'Wow, you guys have grown a lot.' So that makes me feel kind of good. Is it all ready to pop into the big leagues next year? No, not all of it. Is some of it? Probably. Probably some. We have to just keep making decisions that don't jeopardize our health or put us in a financially unhealthy situation."

Eppler, sitting near the back of his room at the Mandalay Bay in Las Vegas, took some time to ponder what could've been as Day 1 of the Winter Meetings was winding down Monday night.

The Angels entered this past season with a legitimate chance. They had re-signed Justin Upton, snagged Shohei Ohtani, added Zack Cozart and Ian Kinsler, and were returning a talented starting rotation with upside. But they wound up utilizing a franchise-record 35 pitchers. Four of the starters they were counting on -- Ohtani, Garrett Richards, J.C. Ramirez and Matt Shoemaker -- combined to make 29 starts. A team that sat in first place in the middle of May finished 80-82 and missed the playoffs for the eighth time in nine years.

"I really would've liked an opportunity to see our starting pitching get through 22, 24, 25 starts," Eppler said. "That would've been interesting to watch because last year at this time, or shortly after this time, I think there was a lot of people that worked inside of Angel Stadium, or followed our club, or employees of the Angels, that were feeling pretty good with signing Upton and Shohei and Cozart and Kinsler. There was some momentum."

Eppler -- in need of a starting catcher and lots of pitching, for his rotation and for his bullpen -- is trying to recapture the momentum without interrupting the progression.

The rest of his division offers a striking departure in philosophy. The Houston Astros went through a complete teardown, resulting in three consecutive 100-loss seasons, and emerged from it a juggernaut. The Texas Rangers have entered into a rebuilding phase after making five trips to the postseason from 2010 to 2016. The Seattle Mariners kick-started their own rebuild this offseason, parting with the likes of Robinson Cano, Edwin Diaz, James Paxton and Jean Segura.

In 2018, six teams won at least 95-plus games, and eight others lost at least that many. The league lived in the extremes. The standard deviation of run-differentials in the American League was the highest it had been, for either league, since 1969, according to research from ESPN's Bradford Doolittle.

At least six AL teams -- the Toronto Blue Jays, Baltimore Orioles, Detroit Tigers, Kansas City Royals, Rangers and Mariners -- are rebuilding in some way. The Chicago White Sox might still be, too. The Oakland Athletics and the Rays are not, but they also won't be spending much money.

The Angels will, to some extent, as evidenced by their aggressive pursuit of Patrick Corbin and Nathan Eovaldi earlier this offseason. The uncertainty surrounding Trout means there's no ideal approach. A complete rebuild would consist either of trading Trout or ensuring that he will eventually walk away, but it would also accelerate the next phase. Going all-in could set the franchise back decades, and Trout might still leave regardless. Nine for IX From ESPN's award-winning documentary series. Watch on ESPN+

The league seems split. One executive believes the Angels should "go all-in" because Trout is "a once-in-a-century player." One longtime, West Coast-based scout said the Angels should "trade Trout and start over" because "they can't spend their way out of it."

"They're in a tough spot," another front-office member said. "I think you either have to trade Mike, or you have to blow past the luxury tax and go all in."

The Angels won't do either. With Trout and Ohtani, who will be relegated to only hitting next season as he recovers from Tommy John surgery, their floor is high. FanGraphs currently projects the Angels to win 83 games in 2019, which would put them one win shy of the Rays for the second AL wild-card spot, according to those projections. If the Angels acquire legitimate top-of-the-rotation starters and back-of-the-bullpen arms, the number of wins will grow.

But the Angels will only reach so far. In three prior offseasons, Eppler has shied away from doling out big contracts to aging veterans and hasn't traded elite prospects unless the return was a young, controllable player. He'll keep it that way.

"I just want to make good decisions for the organization," Eppler said. "I don't want to put us in a tough spot."