For 15 years - but especially for the last eight years - they tried to find the right combination of talent, character and toughness to win a championship. And when they finally found it this season, the Nationals enjoyed one of the greatest October runs in baseball history.

So it’s only natural to now wonder how they might best try to put themselves right back in the same position next October in search of back-to-back titles. And the easiest answer is: Just keep the band together.

Why wouldn’t the Nationals want to preserve their World Series-winning roster as much as possible? It was good enough to produce the best result in franchise history and cement legendary status in this town forever. Why mess around with something that has already proven it works?

Because it’s never as easy as it sounds. And because plenty of teams over the years have found out the hard way that it can be dangerous to put heart before head when assembling a roster.

No major league ballclub has won back-to-back titles since the Yankees’ three-peat from 1998-2000. No National League club has won two in a row since the Reds in 1975-76.

It hasn’t been for lack of trying. Every champion - well, every champion aside from the random Marlins teams that won in 1997 and 2003 and then immediately dismantled the roster - returns the following season with a roster full of returning heroes and perhaps a few key additions meant to supplement the core that already was in place.

And that’s exactly what the Nationals will do. Their 2020 roster is guaranteed to include Max Scherzer, Patrick Corbin, Aníbal Sánchez, Trea Turner, Juan Soto, Victor Robles, Adam Eaton, Kurt Suzuki and Sean Doolittle. And there’s a pretty good chance it will also include Stephen Strasburg and Ryan Zimmerman.

That’s a lot of returning talent, and it will instantly make this team a favorite at least to return to the postseason, if not return to late October.

But the Nationals will be tempted to return even more key figures from this year’s squad. Anthony Rendon. Howie Kendrick. Asdrúbal Cabrera. Matt Adams. Gerardo Parra. Daniel Hudson. Yan Gomes. They’re all free agents, but all could be brought back at the right price. And most would rejoice at the idea of keeping the band together to make another run.

But is that actually the smart thing to do? This is where things get tricky, and front office executives have to be willing to look at the recent past for cautionary tales.

Tops on that list are the Phillies. One decade ago, they were the crown jewel of baseball, having won the 2008 World Series and having returned to the Fall Classic the following year. They did so with a roster that stayed together for a very long time, thanks to a bunch of contract extensions.

Between 2007 and 2013, the Phillies re-signed the following players to new contracts: Chase Utley, Cole Hamels, Brad Lidge, Shane Victorino, Ryan Howard, Jimmy Rollins and Carlos Ruiz. The only prominent player from their championship squad who didn’t sign an extension to stay in Philadelphia, as it turns out, was Jayson Werth, who signed with the Nationals in 2011 and helped build the foundation for long-term success here.

In that time, the Phillies also loaded up with other big-name acquisitions meant to help them win more titles, headlined by starting pitchers Roy Halladay, Cliff Lee and Roy Oswalt.

And what did they get for all that? They returned to the World Series in 2009 but lost to the Yankees. They returned to the postseason in 2010 and 2011 but didn’t advance far. And they haven’t had another winning season since. They’ve finished third in the National League East twice, finished fourth three times and finished dead last three times. Only in the last two years have they finally shed themselves of those albatross contracts and had the money to acquire a new crop of big-name players to try to help them get back into regular contention.

The Nationals face a situation that is starkly different in some ways. Far more of their key championship contributors were veterans on the verge of free agency. And some other key players are already under team control for several more years, either because of previously signed long-term deals (Scherzer, Corbin) or the fact they’re too young to be approaching free agency yet (Soto, Robles, Turner).

But there will be serious temptation to try to bring back as many of those new free agents as possible, ignoring their advanced ages or likelihood of performance drop-off.

So many things went right this season. It would be foolish to assume they’ll all go right again if everyone’s brought back next season.

This is when it all comes down to an internal battle between the heart and the head. The heart says: “Bring ‘em all back, no matter the cost!” The head says: “The odds of lightning striking twice in a row are awfully slim.”

So you wanna be a general manager or owner? Here you go. Good luck making the right decision.