LOS ANGELES — The great thing about baseball? All 25 players on the roster matter. Take Game 7 of last year’s World Series, when Michael Martinez, essentially the 25th guy on Cleveland’s roster, was forced to bat in the bottom of the 10th inning after entering earlier as a defensive replacement. He made the final out against reliever Mike Montgomery, who while not quite the last man on the Cubs’ roster, was the fifth pitcher used by Joe Maddon in the game.

So pay attention to Tuesday’s announcement of the final rosters. The big addition, of course, will be the return of All-Star shortstop Corey Seager to the Dodgers’ lineup, after he missed the NLCS with a lower back strain. Charlie Culberson, who started three games at shortstop in the NLCS after starting just one game at shortstop during the season, was kept on the roster.

The key for the Dodgers is getting their No. 2 hitter back. “I feel good,” Seager said Monday. “They tested everything they needed to test. Took live [batting practice] yesterday. That was kind of the last box I needed to check.”

Culberson is not only insurance in case Seager aggravates his back, but he could also serve as a defensive replacement or start at shortstop in Houston with Seager a DH option. In the NLCS, Culberson started against a lefty starter, with Chris Taylor playing shortstop against right-handed starters. That could mean Culberson starts in a potential Game 5 against Dallas Keuchel.

Here are some other notes on the expected rosters:

Bullpens

The trend of relying on more innings from the bullpen has continued this postseason. Check out the percentage of innings thrown by starters in the postseason over the years, along with ERAs of starters and relievers and the percentage of seven-inning starts:

The starters made a late surge to even get to 54 percent of total innings, but note that the starter has made it through seven innings about once every seven starts the last two postseasons. And certainly don’t expect any complete games, even from Justin Verlander: There have been just five in the World Series this century (Johnny Cueto, Madison Bumgarner, Cliff Lee, Josh Beckett and Randy Johnson).

All that means is that we’ll see plenty of relievers. Dave Roberts has been pulling his starters before 90 pitches — only Kershaw in a Game 1 blowout in the NLDS exceeded 90. We know how dominant Kenta Maeda, Brandon Morrow and Kenley Jansen have been. Maeda has pitched five perfect innings in the postseason and could be an even bigger weapon in this because Roberts wants to match him up against right-handed batters. Houston’s lineup leans right-handed at the top with George Springer, Alex Bregman, Jose Altuve and Carlos Correa. Maeda had a significant platoon split in the regular season (his OPS allowed against right-handers was 134 points lower), but Roberts won’t hesitate to use him against the top of the order.

What will be more interesting is how Roberts handles the situation if his starter gets knocked out early. Maeda or Ross Stripling could be the long man. Perhaps realizing they needed an extra long man, the Dodgers added a 12th pitcher, removing third catcher Kyle Farmer and adding Brandon McCarthy, who made 16 starts with a 3.98 ERA, although has pitched just six innings since July 20 and wasn’t on the roster the first two rounds.

We’ll also see if he can get Tony Watson and Tony Cingrani into games. Watson has faced 13 batters in the postseason, six of them left-handed. Five of the seven batters Cingrani has faced have been left-handed. The matchup options on the Astros are limited, however, with Josh Reddick and Brian McCann the only lefty starters (although backup outfielder Derek Fisher could be a pinch-hitting option). Reddick is certainly somebody you want to get the platoon advantage on. While he hit .315 against lefties, 12 of his 13 home runs came against righties.

For the Astros, we have no idea what A.J. Hinch will do with his bullpen, given his sudden fixation on some small sample size results. He’s also at a disadvantage since Francisco Liriano is the only lefty in his bullpen and the Dodgers are loaded with five left-handed bats in Seager, Cody Bellinger, Joc Pederson, Chase Utley and Andre Ethier. Hinch used Liriano for just one inning in the ALCS in a five-run deficit. Given that Liriano was moderately tough on lefties (.247/.300/.355), you have to think we’ll see him at some point for some matchups against Seager, Bellinger or the other lefties.

Because of the Dodgers’ lineup balance, Hinch is simply going to have trust some of his righty relievers against those lefties at some point. You have to think he’ll give another chance to Chris Devenski, even though seven of the 16 batters he’s faced in the postseason have reached base. Because of his great changeup, Devenski held lefties to a .111 average. Will Harris is the other righty reliever with a good split, holding lefties to a .606 OPS.

Bench guys

The Astros lose their DH in the games at Dodger Stadium, but that’s not a huge loss. Carlos Beltran didn’t have a good season; Evan Gattis started Games 6 and 7 of the ALCS. Beltran will be a pinch-hitting option, but it will be interesting to see if Gattis starts any games at catcher. He started one game behind the plate in the ALCS, when CC Sabathia started. McCann hit .227/.324/.412 versus lefties and will start against Clayton Kershaw in Game 1 and probably Game 2 against Rich Hill, who had an extreme reverse platoon as left-handed batters had a .407 OBP against him. That probably relegates Gattis to coming off the bench until a Game 4 start at DH against Alex Wood.

Roberts has a more complicated lineup. Utley and Logan Forsythe platoon at second base while Pederson or Ethier will platoon in the outfield with Enrique Hernandez. He’s not afraid to pinch hit in the middle of games at those positions, but he has to worry about being too aggressive or you can run out of bench players in an NL game where you need to hit for the pitcher. Hinch will stick with his eight regulars unless he double-switches somebody out of the game.

Deep pitching staff

One area the Astros have the advantage is maybe an extra-inning game where both teams have burned through their top relievers. With Hinch suggesting Lance McCullers will start Game 3 of 4, that means Collin McHugh will once again be available in the bullpen. McHugh didn’t join the team until late July, but had a 2.61 ERA over his final eight starts. If Hinch calls up McCullers in relief, he has McHugh as a possible starter in his back pocket.

The Dodgers, meanwhile, have Maeda, but he’s become an important setup guy. That leaves Stripling as the other long guy with starting experience, but he’s been used sparingly, with just one inning through two rounds. That’s also the disadvantage of carrying two left-handed specialists in Watson and Cingrani. If a game goes extra, Roberts will have already used them or be forced to use them against a string of right-handers.

Pinch runners

Don’t expect too much with the running game from the Astros. They’ve attempted just two steals in their 11 playoff games. The one guy who is easy to run on is Jansen, as base stealers were 11-for-11 against him. The Dodgers have tried eight steals in eight playoff games and the Astros are easy to run on — McCann was just eight for 54 in throwing out runners and Gattis four for 39. The Astros also led in wild pitches, so Dodgers baserunners will definitely be extra alert.

There have been just 11 pinch-running appearances in the postseason, and eight of those came in AL games. The Astros used Fisher twice and Cameron Maybin once, but all three times in the DH spot — twice for Gattis, once for Beltran. McCann is one of the slowest runners in the league and would be a guy to run for late in a close game. Roberts has used one pinch runner, using Culberson for Yasmani Grandal.

The 25th man

Houston’s 25th man is third catcher Juan Centeno, who allows the Astros to DH or pinch hit Gattis and still have a backup for McCann. He batted 57 times and while he hit two home runs, he has just five home runs in 2,000 minor league plate appearances.

Based on regular-season playing time, Culberson is the Dodgers’ 25th man given he had just 15 plate appearances. He already made an impact in the NLCS, going 5-for-11 and making a couple of nice defensive plays.

Will either guy have an influence on the final outcome? Don’t be surprised … especially if we go seven games again and that seventh game goes into extra innings. Hey, we can hope …