WASHINGTON -- So you think you’ve got this World Series figured out? Be careful about jumping the shark, even the Baby Shark. You’re right, the Nationals couldn’t have had a more impressive start than winning two road games over the Astros.

Now, believe it or not, this World Series is about to get really interesting, if not a little bit weird, as the Nationals roll back into their home ballpark for Game 3 on Friday.

You wait 86 years for a World Series, and it should be a baseball tidal wave of packed houses, oceans of red and Baby Shark singalongs. To Washingtonians of a certain age -- those who endured 33 summers without a team -- this World Series is an event they simply did not think would happen.

Way more than the ballpark and city are about to change. So before we crown the Nationals, here are four ways the World Series changes as it moves to Nationals Park:

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1) Lineup changes
Astros: With no designated-hitter spot available at this National League park, manager AJ Hinch says he’s weighing how and when to use rookie DH Yordan Alvarez, who hit 27 home runs in 84 games and made a really good lineup historically good. As much as he’d love to have Alvarez’s bat in the lineup, the Astros’ run prevention would take a hit with him playing left field. Hinch said Alvarez will play in the outfield at some point this weekend, but it may not be in Game 3. Besides that, the value of having Alvarez available for a key at-bat off the bench would give the Astros a threat they don’t usually have. Offense isn’t something the Astros can afford to lose much of considering they scored seven runs in Games 1 and 2 and hit .179 in the American League Championship Series.

Nationals: No more DH duty for Howie Kendrick unless the series returns to Houston. However, Kendrick’s offense is so important to the Nationals that manager Dave Martinez almost certainly will surrender a bit of defense to deepen his lineup by starting Kendrick at second base with Asdrúbal Cabrera available off the bench. It’s a risk/reward calculation that has helped the Nationals win eight straight postseason games.

Advantage: Nationals

2) Rotations
Astros: Hinch has a laundry list of decisions to make. Does he start rookie right-hander Jose Urquidy in Game 4 or pitch Gerrit Cole on short rest? What can he expect from Zack Greinke in Game 3? Greinke has a 6.43 ERA in three postseason starts and has finished five innings just once. If Hinch needs four or five innings from his bullpen, that leaves him in a tougher situation for Game 4, which could be an elimination game.

Nationals: Aníbal Sánchez has made two starts this postseason and allowed one earned run in 12 2/3 innings, and his emergence has given Martinez the flexibility to use other starters in relief. Now as the Nationals look to close things out, they have Sanchez and Patrick Corbin lined up for Games 3 and 4 and Max Scherzer for a potential Game 5.

Advantage: Nationals

3) Bullpens
Astros: Hinch still has trust in Will Harris and Joe Smith. After that, there’s some uncertainty. Ryan Pressly has an 18.90 ERA in seven postseason appearances, but he still feels good and has induced enough soft contact that the Astros said he’s part of the late-inning mix. Closer Roberto Osuna gave up a booming game-tying home run to the Yankees’ DJ LeMahieu in Game 6 of the ALCS, but he has had a solid postseason.

Nationals: The Nationals could be playing three days in a row for the first time this postseason, so that means a thin bullpen will be tested in a big way. Until now, Martinez has been able to use a starting pitcher as a reliever to get the game to late-inning arms Tanner Rainey, Daniel Hudson and Sean Doolittle. That’s probably not going to be possible this weekend, so the World Series may come down to the Nationals getting six or seven innings from their starters, or simply wrapping up the Series in four games.

Advantage: Astros

4) Pitchers hitting
Astros: Game 3 starter Greinke prides himself on his hitting and has nine home runs. He also has a .225 career batting average. That’s really good for a pitcher, but it still creates a hole at the bottom of the lineup and could force Hinch to make pinch-hitting decisions earlier than is comfortable given the 0-2 hole in which the Astros find themselves this Series. With rookies Alvarez and Kyle Tucker available off the bench, Hinch has good options.

Nationals: Martinez has such a thin bullpen that he’s probably going to have to let his pitchers hit even in situations where he might not during the regular season. That’s going to give the Astros some flexibility to work around the seventh and eighth hitters in the Nationals’ order at times.

Advantage: Astros