What's the hardest thing to do in sports? The answer will probably vary depending on the person you ask. Some may say that winning a championship is the most difficult task to accomplish, and they're definitely not wrong.

But others may say that asking a title-winning club to turn around and do it again the following year is the hardest thing to do in sports. And they're not wrong either.

The evidence of this is clear in Major League Baseball. No ball club has won consecutive championships since the New York Yankees three-peated from 1998 to 2000. Heck, since that dynasty ended, only three teams -- the Philadelphia Phillies (2008-09), the Texas Rangers (2010-11), and the Kansas City Royals (2014-15) -- have even reached the World Series in consecutive years. Of that trio, only the Phillies had a chance of winning back-to-back titles.

Knowing recent history, it's easy to think that we'll see a duo other than the Houston Astros and Los Angeles Dodgers in next year's Fall Classic. And you know what? There's a pretty good chance of that -- after a 162-game season is used to figure out which teams are the best, anything can happen in a best-of-five or best-of-seven series (just ask the 2017 Cleveland Indians).

While the Astros and Dodgers took very different roads to reach the World Series, what we can be rather certain of moving forward is that they've each set themselves up well to have more than a decent chance of making deep runs in October multiple times in the coming years.

The Astros' Future

Houston has showed a willingness to spend money when necessary, evidenced by taking on contracts for Carlos Beltran, Brian McCann, and Josh Reddick last winter, along with Justin Verlander prior to the waiver trade deadline. But even with all that spending (among some other moves), their 2017 payroll settled in at just shy of $150 million, which was also a shade below the league average.

That's because their complete and painful rebuild allowed them to build a nucleus of young and inexpensive talent. The below table displays Houston's top-five position players and top-five pitchers with regard to fWAR from this past season, their 2017 salary (per Spotrac), and the dollar value of their performance (Dollars), which is the amount of money a player's production would be worth on the free agent market.

If you're keeping track at home, Houston spent less than $35 million for these 10 players, which produced a total fWAR of 39.1. That's what you call a good return on investment.

Like every other team this winter, the Astros will have some questions that need to be answered prior to 2018, and it wouldn't be far to project another 100-win season for them. But for a squad that only has five players headed for free agency (Francisco Liriano, Luke Gregerson, Tyler Clippard, Carlos Beltran, and Cameron Maybin), they're in awfully good shape to adequately defend their title next year.

While it'll be difficult to lock up all of their nucleus for the long term, one of the biggest benefits about rebuilding an organization is getting the production that Houston has received for cents on the dollar. Excluding Charlie Morton and Marwin Gonzalez, everyone from the above table is under team control through the 2019 season, while Giles, Peacock, Bregman, and Correa all still haven't even begun their arbitration years yet.

These young players will continue to get expensive as they go through arbitration, but Houston also hasn't bogged themselves done with tons of long-term commitments at the moment. They currently have $83.825 million on the books for 2018, with that number dropping down to $57.9 million for 2019, and $26.4 million for 2020 (before any potential long-term extensions).

The Astros were really good this year, and that dramatic rebuild has set them up to remain good for the next handful of seasons. They're right in the middle of their competitive window and are fortunate to already have a championship in tow.

The Dodgers' Future

On the other end of the spectrum is Los Angeles, whose $265 million payroll in 2017 paced the league for the fourth consecutive season. It's easy to look at this number and make assumptions about the on-field product, but that also wouldn't be fair to L.A. The players that made up just under 40% of their 2017 payroll weren't even on the World Series roster.

The Dodgers are one of a select few teams that can spend money like this, and they've taken advantage of it. Similar to Houston, L.A. also has a nucleus of talent they're getting top-tier production from for cents on the dollar, like Corey Seager, Cody Bellinger, Chris Taylor, and Alex Wood. They also have two other important assets locked into long-term deals in Justin Turner and Kenley Jansen.

While the conversation for Houston mostly revolves around how they're going to eventually pay their talent, it revolves around the money that will soon be available for the Dodgers.

Los Angeles' current commitments for 2018 stands at about $177 million. They get some relief in the fact that both the contracts of Andre Ethier ($17.5 million salary in '17) and Carl Crawford ($21.86 million) come off the books. If we look ahead to 2019, Adrian Gonzalez and his $21 million salary will also no longer be on the payroll, bringing their current commitments to $116 million. Some of these savings will go to Turner ($19 million salary in '19) and Jansen ($18 million) because their contracts are backloaded, but this gives the organization tremendous flexibility to basically do whatever they want.

Their young stars will eventually need to get paid, but the Dodgers have shown they have no problem doing that when the time comes. For whatever their roster needs are, they have the luxury of using a top-graded farm system to either insert more cost-effective production or use them to acquire someone via trade. They could always turn to the free agent market, too, which will have a number of elite players looking for huge contracts following the 2018 campaign. You know, the kind of contracts the Dodgers are used to dealing with.

The Astros and Dodgers once again find themselves in similar, yet different situations when looking ahead. We won't know for sure until games are played on the field, but these two organizations have set themselves up well with a tremendous blend of young talent and declining future commitments to continue making deep runs into October for the next few years.