Just three weeks remain in the 2018 MLB regular season, and there are still 15 teams in contention for the 10 playoff spots.

The American League is all but decided, with the Tampa Bay Rays and Seattle Mariners still hanging around as long-shot contenders. The AL East and AL West titles are up for grabs.

In the National League, the picture is far cloudier.

Three teams are still in the running in both the NL Central and NL West, while the NL East is a two-team battle. That leaves the five clubs that don't claim a division title in the running for the wild-card berths.

Ahead is an updated look at the postseason odds for each of those 15 contenders, with the odds based on recent performance, remaining schedule and expectations for the final three weeks.

AL East

Boston Red Sox (99-46, Clinched)

The Boston Red Sox have a comfortable nine-game lead over the rival New York Yankees, and aside from a hiccup against the Houston Astros over the weekend, they've shown no signs of slowing down.

They do still have six games left against the Yanks—including three at Fenway Park to wrap up the regular season—so the division title is by no means decided.

But one way or another, Boston is a lock to be part of the postseason picture after clinching a spot on Tuesday.

Getting ace Chris Sale back up to speed after a month on the disabled list and keeping his balky left shoulder healthy will be the key over the final three weeks.

Odds: 0/1 (100 percent)

New York Yankees (90-55)

Even if they don't catch the Red Sox, the Yankees are a lock to play in October.

The bigger question is whether they'll be hosting the AL Wild Card Game or heading to Oakland for that win-or-go-home contest.

The Yankees close the season with a seven-game road trip against the red-hot Rays and the Red Sox, so the road ahead is not an easy one.

They hold a two-game lead over the Athletics in the wild-card standings. New York has an excellent 48-24 record at Yankee Stadium, so winning the right to host that game would be significant.

Odds: 0/1 (100 percent)

Tampa Bay Rays (79-65)

The Rays still have a virtually impossible uphill climb if they're going to reach the postseason, but they deserve a tremendous amount of credit for even being part of the conversation.

Just one game over .500 at 62-61 on Aug. 18, Tampa Bay has gone 17-4 with a plus-53 run differential in its last 21 games.

The Rays' unorthodox approach with their pitching staff has resulted in a 3.67 ERA, good for fifth in the majors and third in the American League.

A lot will have to break right for the Rays to bridge an 8.5-game deficit in the wild-card standings with just 18 games left on their schedule. But this late-season push could serve as a valuable springboard into next season. The A's went on a similar run to close the 2017 season, and look where they are now.

Odds: 100/1 (1 percent)

Non-contenders: Baltimore Orioles, Toronto Blue Jays

AL Central

Cleveland Indians (82-63)

The Cleveland Indians haven't clinched the division yet, but they will.

With a 15.5-game lead over the Minnesota Twins, their magic number to secure their third straight AL Central title is just three.

To put that another way, even if the Twins win every game the rest of the way, the Indians could go 3-14 in their final 17 games and still win the division.

The real test for Cleveland will come once the postseason starts. The AL Central has been a joke this season, and that has meant a low-intensity second half.

Can they amp things up when the games matter again?

The core group's prior postseason experience should serve the team well when it does come time to flip that switch.

Odds: 0/1 (100 percent)

Non-contenders: Chicago White Sox, Detroit Tigers, Kansas City Royals, Minnesota Twins

AL West

Houston Astros (91-54)

The reigning World Series champions have the game's best pitching staff (3.10 ERA) and a stacked offense (5.0 runs per game), yet they've been unable to pull away from the upstart Athletics.

The two teams are finished playing head-to-head, and Houston closes the season with 10 games against non-contenders, so it's in excellent position to capture a second straight division title.

Trying to avoid the Wild Card Game is all the incentive the Astros need to keep the pedal to the floor.

The second-half breakout of first baseman-designated hitter Tyler White (144 PA, .328/.389/.664, 8 2B, 10 HR, 34 RBI) and how All-Star Charlie Morton fares after coming off the disabled list Saturday will be key factors.

Odds: 0/1 (100 percent)

Oakland Athletics (88-57)

The Athletics have gone 59-29 since June 1, a record surpassed only by the Red Sox (60-28), and they're on the cusp of reaching the postseason for the first time since 2014.

That's thanks in no small part to the contributions of unheralded veteran starters Trevor Cahill (19 GS, 6-3, 3.77 ERA), Edwin Jackson (14 GS, 5-3, 3.26 ERA) and Mike Fiers (7 GS, 5-0, 2.72 ERA with the A's).

Will that trio be up to the task in October?

That remains to be seen, but with an 8.5-game cushion in the wild-card standings, there's a good chance we'll find out.

Odds: 1/50 (98 percent)

Seattle Mariners (79-65)

The Mariners have not reached the postseason since 2001—the longest drought in baseball—and it looks like that dry spell will stretch at least one more year.

The M's were just a half-game back in the AL West on July 3, but they went 8-13 in the rest of July and 12-16 in August.

Regression by the starting rotation has been the biggest issue, and left-hander Marco Gonzales (7 GS, 2-4, 6.75 ERA) in particular has struggled mightily since the All-Star break.

With three games remaining against each the Astros and Athletics, the Mariners could make a run, but nothing in their performance over the past two months suggests they'll get hot.

Odds: 100/1 (1 percent)

Non-contenders: Los Angeles Angels, Texas Rangers

NL East

Atlanta Braves (81-64)

The Atlanta Braves have held at least a share of the NL East lead since Aug. 12, and that lead is up to a season-high 6.5 games as the Philadelphia Phillies have faded.

After slumping in July, the Braves bounced back with a 17-13 August that featured a plus-28 run differential. They look destined for their first playoff berth since they embarked on a full-scale rebuild.

Rookie Ronald Acuna Jr. is hitting an eye-popping .327/.419/.699 with 18 home runs and 12 steals in 51 games since the All-Star break. It will be hard not to draw comparisons to Andruw Jones and the 1996 postseason if Atlanta makes a run in October.

In order for that to happen, the starting pitchers will need to hold up their end of the bargain, with trade deadline pickup Kevin Gausman and breakout star Mike Foltynewicz shouldering the load.

Odds: 7/93 (93 percent)

Philadelphia Phillies (74-70)

The Phillies still have seven games left against the Braves, so they're not cooked yet, but momentum is not on their side.

A 15-11 July that coincided with Atlanta's 10-13 mark vaulted Philadelphia into first place, but it's 15-22 since the start of August, including a brutal 2-8 with a minus-20 run differential since the calendar flipped to September.

Besides Cy Young Award candidate Aaron Nola, the starting rotation has run out of gas, and at the same time, the bullpen has struggled to close games.

This is still a team on the rise, and there are plenty of battles with the Braves for division supremacy forthcoming, but it looks like 2018 belongs to Atlanta.

Philadelphia is still alive in the wild-card race, but it's 6.5 games back and would have to leapfrog three teams to move into the No. 2 spot.

Odds: 19/1 (5 percent)

Non-contenders: Miami Marlins, New York Mets, Washington Nationals

NL Central

Chicago Cubs (84-60)

The Chicago Cubs are not playing their best baseball with a 3-5 record in their last eight games. As a result, their division lead—which stood at five games Sept. 2—has shrunk to just two.

But even if they are overtaken by the Milwaukee Brewers, the Cubs are in solid position to claim a wild-card berth.

Starting pitching continues to be the biggest question mark, and the staff as a whole has posted a 3.95 ERA (12th in MLB) since the All-Star break. That's a considerable slide from the 3.56 ERA (fourth in MLB) it posted during the first half.

Three games with the Cincinnati Reds, three with the Chicago White Sox and four with the Pittsburgh Pirates make for a favorable schedule, but three against the rival St. Louis Cardinals at Wrigley Field to close the season could be huge.

Odds: 1/99 (99 percent)

Milwaukee Brewers (83-63)

The Brewers have appeared to fade several times this season, but they've always righted the ship. As a result, they're poised to reach the playoffs for the first time since 2011 and just the fifth time in franchise history.

Things were looking grim after a 5-10 stretch to begin August, but they've rallied to go 15-6 with a plus-22 run differential in the 21 games since.

That impressive stretch includes a 3-2 record against the Cubs, and while Milwaukee will finish playing the division leaders Wednesday, its remaining schedule is favorable.

That includes six games with the Pirates, three with the Reds and three against the visiting Detroit Tigers to close the season, with a three-game set in St. Louis the only matchup with a contender.

Regardless of whether the Brewers win the division or settle for a wild card, a postseason berth looks all but certain.

Odds: 1/49 (98 percent)

St. Louis Cardinals (81-64)

If you had said at the start of the season that Jack Flaherty and John Gant would be anchoring the Cardinals rotation down the stretch, it would not have painted a positive picture of the team's season.

Yet here we are, with those two young starters picking up the slack for a staff that has dealt with injuries and inconsistency and has ace Carlos Martinez serving as the closer.

Despite those issues, the Cardinals ripped off a 22-6 August. In the process, they went from one game over .500 and on the fringe of contention to the driver's seat of the race for the second wild card.

If St. Louis gets in and wins that one-game playoff, watch how the staff is deployed—it has used seven different starters already in September.

The run of success is hard to ignore, but what keeps the Cardinals' odds from being any higher is their reliance on a wild-card berth. At 3.5 games back and with two teams ahead of them, it's unlikely they'll win the division.

Odds: 33/67 (67 percent)

Non-contenders: Cincinnati Reds, Pittsburgh Pirates

NL West

Colorado Rockies (79-65)

That's right, everyone who doesn't live on the West Coast. The Colorado Rockies are in first place in the NL West.

How, you ask?

German Marquez is one big reason. The 23-year-old has stepped into the role of staff ace, going 4-1 with a 2.13 ERA, 0.90 WHIP and 83 strikeouts in 63.1 innings over his last nine starts—all of which qualified as quality starts.

Kyle Freeland has continued to pitch well behind him, closer Wade Davis has finally found his groove, and the offense has never struggled to score runs with Trevor Story and Nolan Arenado leading the way.

With a 7-3 start to September and just three games left against the Los Angeles Dodgers—against whom they are 7-9 with a minus-19 run differential—the division is within reach.

It would be the first in franchise history, and it might be a necessity if they hope to make the playoffs, as the wild-card picture is cloudy at best.

Odds: 33/67 (67 percent)

Los Angeles Dodgers (78-67)

The Dodgers have won five straight division titles for a reason.

And while they haven't hoisted the Commissioner's Trophy during that span, all that postseason experience will come in handy as they look to punch their ticket.

The starting rotation is finally healthy, and when they pitch to their potential, Clayton Kershaw, Walker Buehler, Rich Hill, Alex Wood and Hyun-Jin Ryu stack up to any staff in baseball.

The big concern is a bullpen that has blown nine saves in 21 chances since the All-Star break and has been without all-world closer Kenley Jansen, who rejoined the team Monday after missing time because of an irregular heartbeat.

It's easy to look at the Dodgers roster and call them a playoff team, but they're on the outside looking in.

That's reason enough to keep their odds this low.

Odds: 7/13 (65 percent)

Arizona Diamondbacks (77-68)

A month-by-month look at the Arizona Diamondbacks' record speaks volumes about their inconsistency:

• March/April: 20-8
• May: 8-19
• June: 19-9
• July: 13-13
• August: 14-12
• September: 3-7

At times, they've looked like the team to beat in the crowded NL West, but since the All-Star break, they've settled in as a .500 team, and things have taken a turn for the worse this month.

Arizona is still just 2.5 games back in the division and three games out of a wild-card berth, but with two teams to overtake in the West and two to pass for the second wild-card spot, that's not as promising as it sounds.

Their remaining schedule includes five games against the Rockies, three with the Astros, three with the Cubs and three with Dodgers, which doesn't help their case.

Odds: 47/3 (6 percent)

Non-contenders: San Diego Padres, San Francisco Giants

All stats courtesy of Baseball Reference and FanGraphs, unless otherwise noted, and accurate through Tuesday.