Last year it was the curse of high expectations that many felt doomed the Nationals to mediocrity, but what is it in 2014? The Post Sports Live crew looks at the major hurdles the Nationals face this season. (Post Sports Live/The Washington Post)

Atlanta Braves General Manager Frank Wren had a plan for this offseason: sign contract extensions with the five young players who formed the core of the team that won more regular season games than any in the National League the past two seasons. Practically, Wren didn’t think his plan would ever happen.

“I don’t think we were ever confident,” Wren said last week, sitting in the home dugout of Atlanta’s spring training ballpark. “We felt like we had a shot, out of the initial five that we approached, we thought we could get two or three.”

The Braves’ rapid-fire deal-making as spring training began, then, surprised not only the baseball world but also those inside the organization by signing all five targeted players. Like the Washington Nationals, their NL East rivals, the Braves possess a cadre of talented players either in or entering their prime. Unlike the Nationals, the Braves know for certain which players they will keep and how much they will pay them.

The contracts ranged from $13.3 million over two years (outfielder Jason Heyward) to$135 million over eight years (first baseman Freddie Freeman). Shortstop Andrelton Simmons, right-hander Julio Teheran and closer Craig Kimbrel also agreed to deals of seven, six and four years.

For the foreseeable future, in order to win the division, the Nationals will have to contend with two hulking sluggers, a 23-year-old right-hander who posted a 3.20 ERA in 30 starts last season, the best closer in baseball and perhaps the game’s best defensive player at any position.

In all, the Braves committed $280.7 million dollars for 27 seasons, all of them prime years. The oldest any player will be during his contract is 31, Freeman’s age in the eighth year of his massive deal.

“I think it makes all the difference in the world,” Wren said. “We always keep a five-year running roster. We’ve got a pretty good idea of what it’s going to look like in one and two. Three, four, five are always somewhat of a guesstimate. We’ve got now a number of guys locked in. It makes it easier to plan and to look at the needs going forward.”

When the Nationals plan for their long-term future, they face many guesses. Only Jayson Werth (35), Ryan Zimmerman (29) and Gio Gonzalez (28) are signed beyond 2015 with a specified salary. Shortstop Ian Desmond and Jordan Zimmermann, both all-stars, are scheduled to become free agents after the 2015 season after signing two-year extensions this winter.

Bryce Harper and Stephen Strasburg are under contractual control through 2018 and 2016, respectively, but at no cost certainty beyond the limits of baseball’s arbitration system. The same is true for Wilson Ramos, Anthony Rendon and Ross Detwiler, who can become free agents in 2017, 2020 and 2016, respectively.

On the surface, the Nationals do not need to act with urgency. But as the Braves showed, the best method of securing talent can be locking up players before they’re eligible for arbitration.

Signing extensions with homegrown stars early in their careers has become common practice. The Braves, in the span of three weeks in February, took it to the extreme. They viewed several factors, some league-wide, some specific to their situation.

Most important, they had the players. After conducting a study, the Braves found their players 25 and under generated 18.2 wins above replacement, Wren said. The next highest was the Los Angeles Angels with 12 — and 11 came from Mike Trout. The Braves had more WAR from their under-25 players than the lowest 11 teams in the majors combined.

“We felt like we had a really good, young dynamic young group of players under age 25 that we could extend,” Wren said. “And we’d be capitalizing on their most productive years.”

Across the league, both the quality and quantity of free agents have declined, and many suspect stronger testing for performance-enhancing drugs has resulted in players declining more rapidly from their peak seasons. Sign a free agent to an eight-year contract, and you get the shaky end of his career. Sign Freeman at 24, and you get his entire prime. And the free agent would cost more.

“We are seeing, 30 is 30 again. 32 is 32 again,” Wren said. “And I think that drives a lot of these decisions. Of the five guys we signed, the oldest is going to be 31. We’re getting their prime years, which was part of their strategy.”

The rash of extensions also has created a cycle: As more teams use extensions for their homegrown players, the free agent crop has thinned.

“As more and more teams take on this philosophy, you’re seeing less quality in the free agent market,” Wren said. “And so clubs are looking to keep their own and not have to go into that market. Because it’s not only less quality, but it’s less efficient. You’re at the mercy of a supply-and-demand system. Usually, there’s more demand than supply.”

By acting early in their players’ careers, the Braves bought out several free agent seasons. They used as leverage “zero-to-three” seasons (when players are guaranteed only the league minimum) and early years in arbitration, which are lucrative but a far cry from a free agent payday.

Players also prefer to sign extensions early, because it allows them to enter free agency for a second contract while still young enough to reap a significant deal.

The toughest part about contract extensions, many GMs acknowledge, is finding the right time. With Zimmermann and Desmond, the Nationals may have waited too long. With free agency two years away, they are less likely to trade a huge contract for security. As one player who did not want to be seen as interfering with negotiations put it, they see “the light at the end of the tunnel.”

Tuesday, the Nationals will play the Braves for the second time, another early preview of their battle for the NL East title. In 2012, the Nationals started hot and cruised to first. In 2013, the Braves returned the favor, only more emphatically.

“They had a good offseason,” Braves left fielder Justin Upton said. “They definitely got better. You never expect to run away with it. They obviously got better, so we’re going to have to play better.”

The Nationals have enough talent to challenge and unseat the Braves this season. They also can be sure, in years to come, it will not be getting any easier.