Before the Philadelphia Phillies were the Philadelphia Phillies, they were the Washington Nationals.

It may be difficult to believe now, as the Phillies, who open a three-game series at Nationals Park on Friday night, close in on a fifth consecutive National League East title — a stretch that also includes two pennants and the 2008 World Series title — but there was a time not so long ago when the Phillies were a floundering franchise lacking any sort of legitimacy, and barely any hope.

In a nine-year span from 1994-2002, the Phillies suffered through eight losing seasons, including three with 94 or more losses. By the end of 2002, the Phillies could see a young core of position players taking shape. Jimmy Rollins and Pat Burrell were already in the majors. Chase Utley and Ryan Howard were coming fast. But the franchise’s stabs at signing free agents had mostly come up empty, because of one thing: No one wanted to go there.

Sound familiar? In the winter of 2002-03, the Phillies were roughly where the Nationals were in the winter of 2010-11. And to hear Phillies insiders tell it, the event that allowed the franchise to turn the proverbial corner was the signing that winter of free agent slugger Jim Thome.

“If there was one thing that got us started, it was when Jim Thome came,” Phillies General Manager Ruben Amaro Jr., at the time an assistant to then-GM Ed Wade, said recently. “I think that legitimized what we were trying to do here.”

(UPDATE, 2:08 p.m.: Commenter “bryc3” made such an excellent point in the comments section, I wanted to highlight it here: During those lean years, the Phillies’ attendance was even worse than what the Nationals’ is now. The Phillies drew 1.6 million fans in 2002; the Nationals drew 1.8 million in 2010. Although the Phillies’ poor attendance was partially attributable to the fact they still played in the old Veterans Stadium, they were still drawing just 2.7 million as recently as 2006, in their second season at Citizens Bank Park, ranking ninth of 16 teams in the NL.)

In December 2002, the Phillies had to overpay to get Thome, who was 32 at the time — back then, six years and $85 million was considered an exorbitant amount — but that’s what a losing franchise had to do to change its course. Before the Thome signing, Phillies fans were grumbling that ownership was too stingy with its checkbook. Such talk pretty much ceased that winter.

“This validates us,” then-Phillies manager Larry Bowa said at the time.

“In Jim’s case, we could go beyond the economic norm because of the residual effect,” Wade said then. “He creates a buzz.”

Now does it sound familiar?

For the modern-day Nationals, the Thome parallel, of course, is Jayson Werth. Last winter, the Nationals could see a young core taking shape in Washington — with Ryan Zimmerman, Danny Espinosa, Wilson Ramos, Ian Desmond, Michael Morse, Drew Storen and Jordan Zimmermann having already arrived, and Stephen Strasburg and Bryce Harper on their way (or, in Strasburg’s case, on their way back). But they were finding it impossible to coax major free agents to join the fold. They changed that with one bold stroke, blowing away the field to sign Werth, at a price — seven years, $126 million — that shook the entire industry.

The Phillies didn’t become today’s mini-dynasty overnight. In 2003, Thome’s first season, they jumped from 80 wins to 86, and they have yet to suffer another losing season — while also witnessing the opening of Citizens Bank Park in 2004. But it was 2007 (by which time Thome had been traded) before they won a division title, and 2008 before they topped the 90-win mark.

In the process, the Phillies developed several other pieces who became part of their homegrown core: Cole Hamels, Carlos Ruiz, Ryan Madson and (via the Rule 5 draft) Shane Victorino. And in later years, the bold (and expensive) acquisitions of all-star pitchers Roy Halladay, Roy Oswalt and Cliff Lee helped ensure the franchise maximizes the championship window that opened in the late 2000s.

By no means am I predicting a similar run of greatness for the Nationals. Too many variables remain. For one thing, young players (especially young pitchers) sometimes fizzle out. For another thing, Werth, at least so far, is no Thome. In Philadelphia, Thome picked up where he had left off in Cleveland, hitting 47 homers and driving in 131 runs in 2003, then going 42 and 105 in 2004, before missing most of 2005 with injuries. Meantime, in Washington, Werth was hitting .227 with a .714 OPS (down from .296 and .921 the year before) entering the Phillies series.

And for the Werth signing to make sense in the big picture, the Lerner family needs to continue to show a willingness to spend big, the way David Montgomery has in Philly.

But this much is certain: For the first time since the Nationals arrived in Washington, you can see the outline of a future contender here, and if you want a glimpse of what the Nationals envision for themselves over the coming years, look no further than the team occupying the visitors’ dugout at Nats Park this weekend.