Whenever the Washington Nationals welcome Bryce Harper back, the task at hand will be finally making the most of his presence.

For now, though, it's good enough that he's due back at all.

Harper has sat out the last six weeks with a left knee injury, but his comeback trail should end before the postseason kicks off next Tuesday. He was even rumored to play Monday's contest against the Philadelphia Phillies at Citizens Bank Park before a sudden illness nixed that plan.

"He was actually here before I got here, trying to get well," manager Dusty Baker said, according to Jamal Collier of MLB.com. "You know Bryce; he is champing at the bit to play. So it's just another minor setback."

Harper's only baseball activity since his ugly slip-and-fall August 12 has been running, batting practice and a couple of simulated games, per Patrick Reddington of SB Nation's Federal Baseball. So while he'll be back in a literal sense, the jury's out on whether he'll be back in a figurative one.

Nonetheless, the Nationals have every right to feel giddy.

The 24-year-old has been reminding everyone that he's one of Major League Baseball's best players when he's healthy. His 1.034 OPS, 29 home runs and 4.7 WAR through 106 games gave him a shot to add a National League MVP to a trophy case that already features the 2015 MVP and 2012 NL Rookie of the Year to boot.

"Hopefully he can come back and get his timing back. That's going to be the hardest thing for him," Nats ace Max Scherzer said Sunday, per Collier. "But when you put him back in the lineup, our lineup is scary. We can score runs with the best of them."

Assuming Harper gets his timing back, the Nationals lineup could indeed be back to its full and frightening capacity. Given that Washington is already heading into October with a star-studded starting rotation and a much-improved bullpen, a scenario is forming in which it'll have no excuses not to win it all.

But that sounds like the kind of trap that only a Harper-era Nationals team could spring, doesn't it?

Dawn broke on this era when the Nats drafted Stephen Strasburg at No. 1 in 2009 and Harper at No. 1 in 2010, and it officially came to light when they joined forces on the big club in 2012. Six years in, it's produced a .572 regular-season winning percentage and four NL East titles.

Turning this era into a proper dynasty, however, has proved difficult.

The "D" word can't be entertained until a team has secured several pennants and/or a World Series title. At the least, it needs to win a postseason series. Harper has done his share to help the Nationals achieve these things but not enough to stop the team from face-planting when the going gets tough.

The 2012 Nationals won 98 games and came this close to beating the St. Louis Cardinals in the National League Division Series. Alas, a ninth-inning collapse in Game 5 wasted, among other things, Harper's first postseason home run.

The 2014 Nationals won 96 games and went up against a mere 88-win San Francisco Giants squad in the NLDS. Alas, hitters not named Harper fell into a stupor, and it was over in four games.

Most recently, the 2016 Nationals won 95 games and took a 2-1 lead over the Los Angeles Dodgers in the NLDS. Alas, even Harper's .458 on-base percentage in the series couldn't stop another five-game defeat.

Granted, all this is more pleasant than what came before. Between the franchise's debut as the Montreal Expos in 1969 and its first seven seasons in Washington between 2005 and 2011, the Nationals were a steady sub-.500 team that produced just one postseason appearance.

The fundamental difference is that the pre-Harper clubs had a good excuse for being a perennial doormat: They couldn't compete financially. Low payrolls were a fact of life in Montreal, and the move to Washington only brought slow improvement at first.

But since 2012, it's been a different story:

Spotrac puts the club's 2017 expenditures at about $188 million. So, when everything is taken into account, the Nationals' six-year search for a dynasty will have cost nearly $900 million.

The franchise has thus gone from spending relatively modest dollars on a whole lot of nothing to spending a whole lot of dollars on relatively modest success. While one may be more pleasant than the other, neither is especially fulfilling. 

If there's any hope to be found in these payroll figures, it's that the most expensive Nationals team may also be the best one yet. The path ahead is rocky and littered with pitfalls, however.

The Nationals are projected for an NLDS matchup against the Chicago Cubs, who are a year removed from a championship and in the midst of a red-hot second half. If the Nats survive, they could face the similarly hot Arizona Diamondbacks or the Dodgers, who remain formidable despite their recent slide. 

Regarding the Nats themselves, an offense that's already been slumping could keep doing so if Harper isn't himself. Their starters come with questions too. Scherzer's been up-and-down lately. Gio Gonzalez's good fortune with men on base can't last forever. Nobody ever knows if Strasburg is safe from the injury bug.

Oddly enough, Washington's surest bet for the playoffs might be a bullpen that's been among MLB's best since getting a makeover in July. The irony of that is rich, given that everyone and their uncle had previously been lining up to blame the bullpen for Washington's latest October failure.

But if that October failure does indeed happen, the urge to throw blame around could be overruled by angst over what comes next.

There's no ignoring the ticking clock that's counting down to the end of 2018. When it runs out, there's a good chance that the Nationals will wave goodbye to a host of free agents led by Daniel Murphy, Gonzalez and, of course, Harper himself.

The Nationals have already inked Harper to a $21.625 million deal for 2018. It was a show of good faith, if nothing else. Certainly, bringing home a championship would only strengthen their bond.

But in all likelihood, it'll come down to the bottom line.

With Harper doing the playing and agent Scott Boras doing the negotiating, the slugger's next contract is bound to blow away Giancarlo Stanton's $325 million megadeal and set a new record for the largest in sports history. Such a deal is far, far more likely to come from free agency than from Washington's front office.

If it doesn't happen this year, optimists will note that the Nationals still have one more year to bring home a World Series before the book closes on the Harper era. More pessimistic types will point out that next year's Nats will be an even older version of a team that's already among MLB's oldest at the plate and on the mound.

This season may not be the Nationals' last chance, but it could be their last best chance. If ever they're going to stop wasting these things, now's the time.

All stats courtesy of Baseball Reference, FanGraphs and Baseball Savant. Payroll data courtesy of Cot's Baseball Contracts and Spotrac.