Assessing the factors that will shape September's races

Starting Lineup is a biweekly collection of reporting, observations, and insights from the baseball beat, published every other week during the regular season.

Leading off …

September baseball in the flyover country comprising the American League Central has often been forgettable in the wild-card era.

The division rarely features a World Series contender, let alone multiple playoff berths. It's been a land of low payrolls and some questionable baseball operations groups.

There are only four instances of an AL Central club capturing a wild card in a full season since the three-division era began in 1995: the 2006 Detroit Tigers, 2013 Cleveland Indians, 2014 Kansas City Royals, and 2017 Minnesota Twins. (The Tigers and Royals lost in the World Series in those seasons.)

By comparison, the AL East accounts for 27 wild-card berths (58%) in that span.

One of the more unusual aspects of the 2024 season is that there are wild-card and first-round bye implications in the Central this September.

The Guardians lead the division and have the No. 2 seed. The Twins and Royals hold the second and third wild-card spots. The Central is the only division with four teams at .500 or better.

This improvement could have some staying power. The Royals and Tigers have upgraded their scouting and player-development efforts, joining consistent organizations like the Twins and Guardians.

2. Crown 'em?

What factors could be the difference-makers in the Central race?

The Royals' arrow has been pointing up the most since mid-summer. They held just 25.8% playoff chances on July 9, per FanGraphs' projections. Entering Friday, those chances stood at 83.9%. It's the biggest improvement among AL clubs.

And there are reasons to believe Kansas City can sustain this.

Yes, it helps that the team has an emerging superstar in Bobby Witt Jr., but the Royals have also enjoyed a stable and productive starting rotation.

They rank second in the majors in innings thrown by starters, third in ERA (3.62), and third in WAR (14.9). Seth Lugo and Michael Wacha were two of the best value signings of the offseason - 6.6 combined fWAR for a combined $31 million this season - and Cole Ragans broke out.

That production has shielded the team from one of its weaker units, the bullpen, although it did add Lucas Erceg at the deadline.

Conversely, the division-rival Guardians have perhaps relied too heavily on their great bullpen. They rank 24th in starters innings, and their MLB-best 2.62 bullpen ERA from the first half of the year has fallen to 3.27 over the last 30 days.

3. Home cooking in Cleveland

The Guardians do have one big advantage over the Royals and Twins. Starting on Sept. 12, they play 13 of their final 16 games at Progressive Field. Cleveland has baseball's third-best home record.

A big factor has been Progressive Field dramatically changing into an above-average park for lefties after the offseason removal of some of the upper-deck seating areas, which seemingly created something of a wind tunnel.

According to Baseball Savant's park factors, Progressive Field's rating for lefties has changed from a 94 last season to a 104 this campaign, with 100 being average. The Guardians have logged the second-most left-handed plate appearances (2,655) this year, trailing only Boston (3,034).

Cleveland can also expect some better luck down the stretch. The team owns a lowly .253 average on balls in play over the last 30 days; the league average is .295 in that span.

4. The highest-stakes race

The AL East features the only high-stakes coin-flip race in baseball. One team will earn a bye in the AL playoffs, and the other will be relegated to a wild-card spot.

Heading into the weekend, FanGraphs projected the Yankees with a 56.5% probability of winning the division, with the Orioles at 43.5%. The Phillies and Dodgers enjoy 91% chances of securing first-round byes. The Guardians have a 69% probability of securing the other bye in the AL.

The Yankees and Orioles are typical AL East contenders, ranking first and second in the majors in home runs and second and third in runs scored. But they also have question marks.

Baltimore needs closer Craig Kimbrel to get back on track, and the rotation is thin beyond Corbin Burnes and Zach Eflin. But the biggest key is catcher Adley Rutschman.

Rutschman is in an extended slump, hitting just .212 with two homers in 151 second-half plate appearances. His defense and framing numbers have also regressed. The former No. 1 overall pick hasn't really struggled at any point like this in his young career.

Could fatigue be a factor? Rutschman ranks 12th in the majors in innings caught and third in plate appearance by a catcher. His average exit velocity has fallen from 89.4 mph in the first half to 85.9 mph in the second.

For the Yankees, the bullpen is a mess that needs to be sorted out. The club ranks 27th in bullpen ERA over the last month (5.44). After Clay Holmes blew a lead Tuesday, manager Aaron Boone said he'll have to be "creative" with how the team closes out games.

Only adding Mark Leiter Jr. at the trade deadline may come back to haunt New York.

5. Musical chairs and an SOS alarm

The NL wild-card race features three seats and four teams.

The Mets, Padres, Diamondbacks, and Braves were within three games of each other for the three wild-card entering Friday.

New York's second-half surge is one of the better stories in baseball. Francisco Lindor would be garnering serious NL MVP consideration if it wasn't for Shohei Ohtani.

But the Mets face a problem down the stretch: They have the toughest remaining schedule among contenders with a combined opponents' winning percentage of .534.

The Diamondbacks (.518), Orioles (.515), Royals (.509), and Yankees (.505) are the only other contenders who face remaining slates that aggregate above .500.

Los Angeles (.475) enjoys the 27th-hardest remaining schedule. The Padres (.485), Guardians (.487), Red Sox (.487), and Astros (.491) also have among the most favorable schedules.

6. A super team?

For as well as the Padres and rookie sensation Jackson Merrill are playing, they have a problem: the Dodgers keep playing a little better.

Los Angeles was 21-9 in its last 30 games entering Friday, the best record in MLB over that stretch. The second-best mark? The 20-10 runs by the Padres, Diamondbacks, and Cubs.

The Dodgers will return Yoshinobu Yamamoto to their rotation Tuesday. And the lineup was bolstered three weeks ago by Max Muncy's return after nearly three months on the injured list. L.A. now has five bats with a 120-plus wRC+ mark over at least 200 plate appearances.

Gavin Lux is showing signs of life after struggling for multiple years to live up to his prospect pedigree. He gives the Dodgers an eighth batter with a wRC+ better than the league average.

The bullpen is deeper, too, as Michael Kopech owns a 0.59 ERA and a 20-to-5 strikeout-to-walk ratio since being added at the trade deadline.

7. A 50-50 toss-up

It looks increasingly likely Shohei Ohtani will author the first 50-50 season in MLB history. (Yes, the newly robust stolen-base environment inflates it, but it's a remarkable accomplishment nonetheless.)

In fact, the aggregate of FanGraphs's four projections systems has Ohtani finishing with exactly 50 home runs and 50.3 steals.

If Ohtani has the homers locked down, one figures he'll do everything he can to secure the steals. He owns a 92% success rate on attempts this year.

FanGraphs analyst Ben Clemens ran simulations to ascertain when Ohtani would most likely secure 50-50. That would be Sept. 27 in Colorado (a 6.3% chance). There's a 56% likelihood he secures 50-50 by the end of the season, according to Clemens.

8. Restless in Seattle

Few teams have been as disappointing as the Seattle Mariners this season.

Despite possessing one of the most talented and productive pitching rotations, their playoff chances have fallen from 91.7% in mid-June to 9.4% entering Friday.

The main culprit is a dreadful offensive effort that cost manager Scott Servais and hitting coach Jarret DeHart their jobs last month.

President of baseball operations Jerry Dipoto is reportedly​​​​​​ returning, which might be frustrating for Mariners fans. Seattle only has the 2022 wild-card series win over Toronto in his nine years at the helm.

Dipoto's .510 winning percentage during his tenure is short of his own, controversial aim to win 54% of games over a decade. But that three-percentage point swing is a big deal; only five clubs - the Dodgers, Yankees, Astros, Cardinals, and Guardians - have won 54% of their contests over the last decade.

But there's reason to be patient with Dipoto and his front office. They're adept at finding and developing pitchers like mid-round draft picks Bryce Miller and Bryan Woo.

And there are bats on the way in the coming years to help boost the lineup.

The Mariners have Baseball America's No. 7-ranked farm system, and it's loaded with potential impact bats such as Colt Emerson and Lazaro Montes.

Of course, there could still be a waiting period on some of those bats, meaning Dipoto's brain trust will have to find a way to bridge the gap this offseason. Once a front office begins firing major-league coaches, the clock is ticking on its own tenure.

9. A thinning market

Many teams (hello, Blue Jays) will seek external offensive help this winter after a season in which MLB batters are combining for a .714 OPS, the second-worst mark of the last decade. The free-agent market became a little thinner this week as Matt Chapman signed a $151-million extension with the Giants.

In fact, that leaves the market with only two impact players on the left side of the infield: Alex Bregman at third base and Willy Adames at shortstop.

It'll be difficult to improve externally for the 15 teams featuring below-average OPS marks.

Travis Sawchik is theScore's senior baseball writer