Welcome to our two-part guide to the 2019 MLB season through the lens of our MLB prediction model. In each division, we’ll outline the key teams in the division race, discuss the incoming players who will make the biggest difference and classify the tanking teams you should ignore on principle. Let’s start with the National League:

How Elo is forecasting the NL East race Avg. Simulated Season Chance to… Team Elo Rating Wins Losses Run Diff. Make Playoffs Win Division Win World Series Nationals 1536 89 73 +74 59% 38% 6% Mets 1523 85 77 +36 42 23 3 Phillies 1519 84 78 +28 39 21 3 Braves 1516 84 78 +24 37 19 2 Marlins 1437 64 98 -158 1 <1 <1 Based on 100,000 simulations of the 2019 MLB season Sources: Baseball prospectus, Fangraphs, Clay Davenport

The division race: Welcome to the tightest division race in baseball. Four teams in the East are projected to win at least 84 games, the most in any division this season. The Washington Nationals are slight favorites despite losing Bryce Harper, thanks to an existing core that includes SP Max Scherzer (8.8 wins above replacement last season), 3B Anthony Rendon (5.2), SS Trea Turner (4.4) and 20-year-old LF Juan Soto (3.3) — all of whom were better than Harper last year anyway. Add in a few notable offseason additions, and Washington has a ton of talent. Another team that loaded up this offseason is the New York Mets, who will return a dominant rotation of Jacob deGrom (9.7!), Zach Wheeler (4.3) and Noah Syndergaard (4.1) to go with an overhauled lineup and bullpen. We see them improving substantially on last year’s 77-win record, though it might not be enough to get back to the playoffs. The Philadelphia Phillies have also improved a bunch since last season, when they collapsed down the stretch (and had the run differential of a 76-win team anyway). Staff ace Aaron Nola (7.5) might quietly give deGrom and Scherzer a fight for the title of division’s best pitcher. But like the Mets, Philly could also get caught up in the East’s numbers game. Finally, the Atlanta Braves are the defending division champs, and their award for that accomplishment is the fourth-best forecasted playoff chances this season. Our projections are skeptical about Atlanta’s staff (both in terms of health and performance), and the model generally dings teams the year after making huge leaps in record — the Braves went from 72 wins in 2017 to 90 in 2018 — particularly in the absence of big personnel upgrades. But keep an eye on LF Ronald Acuna Jr. (3.9), who could develop into an MVP-type talent before too long.

The difference-makers: Harper (2.4 WAR) got all the headlines for his move from Washington to Philadelphia, though he might not be the most important new face on his own team. He trails C J.T. Realmuto (4.5) and SS Jean Segura (4.1) in terms of incoming WAR. As for the Nationals, big additions such as SP Patrick Corbin (5.5) and C Yan Gomes (2.5) — as well as top prospect CF Victor Robles — should keep them afloat without Harper. The Mets’ big-name pickups include closer Edwin Diaz (3.3), 2B Robinson Cano (3.1) and C Wilson Ramos (2.5), part of maybe the best influx of net WAR any team added this offseason. (Don’t sleep on prospect 1B Pete Alonso, either.) Finally, the Braves snagged former MVP Josh Donaldson (1.3) in free agency and will give a bigger role to up-and-coming SP Touki Toussaint — though, to the consternation of Atlanta fans, they added little else of consequence for their division-title defense.

Gone tanking: The Miami Marlins. (The less said, the better.)

How Elo is forecasting the NL Central race Avg. Simulated Season Chance to… Team Elo Rating Wins Losses Run Diff. Make Playoffs Win Division Win World Series Brewers 1529 86 76 +42 46% 29% 4% Cardinals 1525 85 77 +38 44 28 4 Cubs 1521 84 78 +23 38 23 3 Pirates 1499 79 83 -21 21 11 1 Reds 1496 77 85 -33 18 9 1 Based on 100,000 simulations of the 2019 MLB season Sources: Baseball prospectus, Fangraphs, Clay Davenport

The division race: This looks like a tough three-team fight at the top. We give a razor-thin edge to the defending division champ Milwaukee Brewers, who bring back a core featuring the NL’s 2018 MVP, RF Christian Yelich (7.6 WAR), plus CF Lorenzo Cain (6.3), 3B Travis Shaw (3.8), 1B Jesus Aguilar (3.2) and a dominant bullpen that ranked among baseball’s best last season. The rotation has question marks, though, including breaking in a couple of young converted relievers in Corbin Burnes and Brandon Woodruff. The St. Louis Cardinals should be right on Milwaukee’s heels either way, thanks to a couple of big-name additions — see below — on top of a deep group that was already good for 88 wins last season. Third baseman Matt Carpenter (4.9) remains an underappreciated WAR star, and 2018 breakout SP Miles Mikolas (4.5) anchors a solid, hard-throwing rotation. Finally, we have one of the most polarizing teams in baseball going into the season: the Chicago Cubs. Baseball Prospectus’s PECOTA projections forecast only 79 wins (!) for the Northsiders this year, and while other systems are higher on the team, the Cubs appear to be far removed from their glory days of 2016. That said, Chicago still has plenty of productive talent, including SS Javy Baez (5.8), SP Kyle Hendricks (3.1) and a pair of likely bounce-back candidates in 1B Anthony Rizzo (2.8) and 3B Kris Bryant (2.1). It would be foolish to discount the Cubs from this division race.

The difference-makers: The biggest NL Central pickup of the offseason belonged to the Cardinals, who traded for 1B Paul Goldschmidt (5.3 WAR) in December. With a 7.9 WAR season under his belt in 2015, Goldy is legitimately capable of mounting an MVP bid. Also of note, St. Louis added RP Andrew Miller (0.3) in free agency; Miller was injured for most of 2018 but isn’t far removed from being a game-changing bullpen weapon. Cardinal pitchers Dakota Hudson and Alex Reyes could also make a difference off the farm. Milwaukee’s consensus top prospect, 2B Keston Hiura, might make an MLB appearance this year, but the Brewers’ most important acquisition was former Dodgers backstop Yasmani Grandal (4.1), a big upgrade over last year’s Manny Pina/Erik Kratz timeshare. As for the Cubs, the meager additions of utility man Daniel Descalso (1.3) and reliever Brad Brach (0.5) may pale in comparison to the impact of getting SS Addison Russell (1.7) back in early May from a 40-game domestic violence suspension.

Gone tanking: Nobody? Although the Pittsburgh Pirates and Cincinnati Reds will struggle to figure into the division battle, both teams are in range of .500. The Pirates are projected to win 79 games, which will presumably help continue their reign as the most average franchise in sports. And the Reds picked up a few name-brand players (RF Yasiel Puig; SPs Sonny Gray, Tanner Roark and Alex Wood) who should help them be more competitive.

How Elo is forecasting the NL West race Avg. Simulated Season Chance to… Team Elo Rating Wins Losses Run Diff. Make Playoffs Win Division Win World Series Dodgers 1562 95 67 +123 79% 66% 13% Rockies 1515 82 80 +13 34 17 3 D-backs 1497 79 83 -19 21 9 1 Padres 1484 75 87 -50 14 6 <1 Giants 1466 71 91 -93 6 3 <1 Based on 100,000 simulations of the 2019 MLB season Sources: Baseball prospectus, Fangraphs, Clay Davenport

The division race: Unlike the other two National League divisions, this doesn’t seem like much of a battle on paper. The Los Angeles Dodgers are the prohibitive favorite here, with a projected 13-win cushion over their next-closest foe. L.A. lost Grandal and Manny Machado in free agency and traded away Puig, but this remains the most impressive collection of players in the entire NL, spearheaded by starters Clayton Kershaw (4.0 WAR) and Walker Buehler (3.4) along with 3B Justin Turner (4.4) and a host of multipositional talents including Max Muncy (4.7), Cody Bellinger (3.9), Chris Taylor (3.6) and Kiké Hernandez (2.9). The Colorado Rockies are the most logical candidates to challenge Dodger supremacy — which they happened to do all of last season, tying L.A. with 91 wins through 162 games and forcing a one-game playoff for the West crown. Colorado brings back 3B Nolan Arenado (5.7) on a fresh extension, but the team lost 2B DJ LeMahieu (2.5) and RP Adam Ottavino (2.3) while adding few impact names. The projections think they’ll be weaker. And it’s not clear how the San Diego Padres (who aren’t tanking anymore but don’t appear ready to contend yet) or the Diamondbacks (who lost Goldschmidt, Corbin and A.J. Pollock) could step up to push L.A. Then again, you could have said something similar last year, and the Dodgers barely managed to win the division.

The difference-makers: This West’s biggest offseason acquisition was easily Machado (6.0 WAR), who signed with the Padres in February. Along with new 2B Ian Kinsler (2.4) and infield prospects Fernando Tatis Jr. and Luis Urias — plus top-40 prospect pitcher Chris Paddack (who could pair with fellow spring breakout Matt Strahm to raise eyebrows his year) — Machado will help make San Diego relevant again, even if its division odds remain slim. As for the Dodgers, they signed Pollock (2.5), a 7-win player back in 2015, and ex-Red Sox reliever Joe Kelly (0.5); maybe young OF Alex Verdugo can also make some kind of dent in a crowded field. Meanwhile, Colorado added 2B Daniel Murphy (-0.1) — who was highly productive in 2016 and 2017 but injured and ineffective in 2018 — and little of note otherwise. The Rockies will look ahead to the future with infield prospects Brendan Rodgers and Garrett Hampson. Arizona made some moves at the margins, but its offseason storyline was mainly about shedding established talent and restocking the farm system. And the Giants had a terrible winter, striking out in the Harper sweepstakes and barely upgrading a roster that won 73 games last season.

Gone tanking: The Arizona Diamondbacks and San Francisco Giants. (Maybe?) The D-backs aren’t bad enough to fully qualify yet, but they seem to be steering in this direction. And while the Giants would never commit to a full tear-down with their attendance numbers being what they are, it’s not totally obvious where the franchise goes from here — with the core of its dynasty eroding and a lack of reinforcements on the way.