Where some things seemed certain just a few short weeks ago, suddenly, every team's perch in the rankings might seem a bit more precarious. The Tampa Bay Rays just swept the Boston Red Sox to put a big dent in Boston's bid to break the single-season team record for wins. And just like that, Boston is no longer our unanimous No. 1, getting four of five votes. We have tight races in both West divisions, the Yankees' perch atop the American League wild-card standings suddenly doesn't seem so secure, and the National League wild-card picture has at least five worthy challengers. And given how quickly teams like the Seattle Mariners and Washington Nationals recently saw their fortunes turn, there's plenty of time for more major changes.

This week, the St. Louis Cardinals' surge under interim manager Mike Shildt carried them back into the top 10, bumping the Philadelphia Phillies, who were this week's biggest fading team with a three-slot drop in our rankings coinciding with their drop in the NL East race. The Arizona Diamondbacks and Colorado Rockies -- whose three-spot gain was this week's largest by any team -- both picked up ground, while the Los Angeles Dodgers spent another week disappointing yearlong expectations that their big-budget superteam was finally going to bust out. The Chicago Cubs may have solved their offensive problems, but they still couldn't crack our all-AL top five. The Cleveland Indians play just nine games against winning teams the rest of the way, which could set them up for another sizzling stretch romp. And with the Oakland A's and Houston Astros primed for their final series starting Monday, this might be the last week we see the Sox, Yankees and Astros holding the top three spots.

This week, our panel of voters is composed of David Schoenfield, Eric Karabell, Tim Kurkjian, Bradford Doolittle and Sarah Langs.

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Record: 90-42

Week 20 ranking: 1

Compared to the rest of their season, the Red Sox are in a slump. The MLB win leaders are 4-6 in their past 10 games, including three losses to the Rays. This has coincided with a slump for Mookie Betts. Boston's right fielder is just 8-for-41 since Aug. 15, including more strikeouts than hits. Over the past three seasons, Betts' strikeout rate ranks as the 14th lowest in baseball. Boston hopes Betts can return to form as soon as possible. -- Dan McCarthy, ESPN Stats & Information

Record: 80-50

Week 20 ranking: 2

The Astros got Jose Altuve back from the disabled list Tuesday, only to have George Springer get scratched with quad soreness. With Springer still sidelined, Altuve, Springer and Carlos Correa have not been in the lineup together since June 25. The Astros are 28-22 in the span when the trio was not available to play together. -- Jacob Nitzberg, ESPN Stats & Information

Record: 83-47

Week 20 ranking: 3

CC Sabathia's resurgence this season has been great news for the Yankees' rotation. Sabathia's 3.30 ERA is on pace to be his best since 2011, the last time he finished in the top five of the Cy Young voting. He has dramatically improved each year since he posted a 5.28 ERA over eight starts in 2014, and he has been excellent of late. He has a 2.18 ERA this month and logged 12 strikeouts on Aug. 7, his third 10-strikeout game over the past five years and his most since Aug. 17, 2016 (12). -- McCarthy

Record: 79-52

Week 20 ranking: 5

The A's head into Houston for a showdown series to start the week, hoping that two of the game's best road warriors help them make the AL West race even more interesting. Khris Davis leads the AL in home runs hit on the road (20), with Jed Lowrie third with 17. And if those games are close, beware -- Davis is also tied for the MLB lead in homers in the seventh inning or later with 14, while Lowrie has 11 of his own. -- Christina Kahrl, ESPN.com

Record: 74-56

Week 20 ranking: 4

Trevor Bauer's stress fracture might scupper his Cy Young hopes while shelving him until at least mid-September, but the Indians' rotation doesn't look like it will keep them from cruising to another AL Central title. The Tribe has gone 14-8 in games started by rookies Shane Bieber and Adam Plutko, while Carlos Carrasco is among the AL leaders since the All-Star break with a 2.23 ERA and a 31 percent strikeout rate in the second half. -- Kahrl

Record: 76-53

Week 20 ranking: 6

The Cubs' offense set a major league record, but not a good one, by scoring exactly one run in five straight games, with the only run in each game coming on a solo home run. The five straight games scoring one run or fewer ties a franchise record as well. So the Cubs attempted to jump-start their offense by acquiring Daniel Murphy from the Nationals; at the time of the trade, Murphy had hit .413 at Wrigley Field, the best average in the history of the stadium (minimum 100 at-bats). -- Nitzberg

Record: 72-58

Week 20 ranking: 8

As the Diamondbacks strive to build a lead in the NL West, Snakes slugger Paul Goldschmidt has put himself in the MVP conversation with the Cardinals' Matt Carpenter and Rockies' Nolan Arenado. After finishing second in the voting twice before and third in another season, this might be his year with Arizona vying to upset the expectations that the Dodgers were supposed to win the division. Goldschmidt leads all of baseball in road slugging (.685) and the NL in road OPS (1.111). -- Kahrl

Record: 73-57

Week 20 ranking: 7

The kids just keep coming, and they're good. When Bryse Wilson made his debut Aug. 20, per Elias Sports Bureau research, the Braves became the third team in the modern era to have three starters aged 20 or younger debut in a season. All three won their starts, including Wilson, who became the youngest Braves pitcher with a scoreless start since Steve Avery on Sept. 21, 1990. -- Evan Wildstein, ESPN Stats & Information

Record: 70-61

Week 20 ranking: 9

Kenley Jansen struggled badly last week after coming back following his diagnosis of an irregular heartbeat, taking two losses and blowing a save. But the Dodgers aren't the only NL West team with problems locking down leads. While the Dodgers have blown eight saves since the All-Star break, so have the Giants, while the Rockies lead with majors with nine. And with the Diamondbacks blowing six of 11 opportunities, there might be a lot of late-game drama down the stretch. -- Kahrl

Record: 73-58

Week 20 ranking: 11

We don't need to chop off the first month and a half of Matt Carpenter's season to make his case for NL MVP. His .963 OPS is second best in the NL behind Nolan Arenado's .973. His 14.8 percent walk rate is top-10 in the NL. He has 4.9 WAR this season, tied for fifth most in the National League among position players. He has been clutch, too -- his 14 home runs in the seventh inning or later are tied for the most in the majors with Khris Davis and lead the NL. On Sunday, he hit four doubles, tying the major league record for a nine-inning game. -- Sarah Langs, ESPN Stats & Information

Record: 71-59

Week 20 ranking: 14

Since July, the Rockies have been one of the best teams in baseball, and an odd development is brewing. In that span, they've had some of the best home pitching in baseball, led by Kyle Freeland. Freeland's 2.27 home ERA this season is on pace to smash the Rockies' franchise record of 2.76, set by Jorge De La Rosa in 2013. -- Wildstein

Record: 73-59

Week 20 ranking: 13

The Brewers took care of the Reds early in the week, winning the rubber game behind another outstanding outing from Freddy Peralta. The rookie held the Reds to just three singles over seven innings, and has allowed just 40 hits in 69⅓ innings this season. Peralta boasts a .167 opponent batting average this season, the lowest among starting pitchers with at least 50 innings pitched. -- Nitzberg

Record: 70-60

Week 20 ranking: 10

Wilson Ramos has been a great addition, although injuries have continued to be an issue. Overall, he is headed toward the second-best season of his career after the 2016 season, when he got injured right before the end of the season. He's hitting .311; he hit .307 that season. He has an .874 OPS; he had an .850 mark that season. That year, Ramos' end-of-September ACL injury prevented him from contributing to the Nationals' postseason run -- and they were bounced in the NLDS (again). Will he get his chance to affect a postseason run this year? -- Langs

Record: 74-57

Week 20 ranking: 12

While notching his franchise-record 50th save over the weekend, Edwin Diaz staked his claim to pitching the greatest relief season in Mariners franchise history. He's second among all relievers in MLB in WPA (and trailing just Blake Treinen among all AL pitchers, to boot). Given the Mariners' routinely narrow margins of victory, he has had to pitch in almost half their games (64 of 131). With five weeks to play, he has an outside shot at Francisco Rodriguez's MLB single-season saves record of 62, having already notched a 12-save month in June. -- Kahrl

Record: 70-61

Week 20 ranking: 16

Tampa Bay has surged with its second eight-game win streak of the season to become just the third team this season to compile more than one win streak of that length, joining division rivals Boston and New York. Over their most recent stretch, the Rays lead the league in batting average and rank second in ERA. Their tactics might be unorthodox, but the team is nine games over .500 this late in a season for the first time since 2013. -- McCarthy

Record: 65-66

Week 20 ranking: 15

The Nationals became sellers, shipping Daniel Murphy to Chicago and Matt Adams back to St. Louis. And while we might have expected the Nationals to go on a run after that -- because That's Baseball -- that didn't happen, as the Nationals were shut out in three straight games through Saturday. That tied the longest such streak in franchise history and was the first time they did so since 2004 as the Expos. They're the first team to be shut out in at least three straight games this season. -- Langs

Record: 63-68

Week 20 ranking: 17

Mike Trout is back and already back to being outstanding. He's on pace for 38 home runs, three fewer than his career high, and for 127 walks, which would shatter his career best of 116. He has a .458 on-base percentage, with his career high being .442. He's also on pace for a career-high OPS and on pace to come just short of a career high in WAR. As for the rest of the team, it hasn't quite gone as planned. The Angels have used a franchise-record 34 pitchers this season and have had 25 players on the disabled list, second most in the majors. -- Langs

Record: 64-67

Week 20 ranking: 18

The Pirates haven't made it easy on themselves with their recent home play. In a crucial August, they're 3-8 at home, all against teams in the playoff race, after posting a .552 home winning percentage through July. They'll see two of those teams, the Cardinals and Braves, on the road this week in what feels like a potential elimination week should things go poorly for the Bucs. -- Wildstein

Record: 65-67

Week 20 ranking: 19

With Buster Posey headed for season-ending hip surgery, it's worth taking a look at his career since he returned at the beginning of the 2012 season following his 2011 injury. He has played 984 games in that time, fourth most in the NL. Three of the top four players in games played in that span are Giants. Andrew McCutchen leads with 1,053 games played, and Brandon Crawford is third in the NL with 1,013. Posey's 984 games are the most of any primary-position NL catcher in that span. -- Langs

Record: 61-69

Week 20 ranking: 20

Things aren't rosy in the Twin Cities right now, but there are a few bright spots. Tyler Austin has been as advertised, hitting four homers in his first 11 games with Minnesota. But the real fun could come with September call-ups, when Twins fans could get their first look at top prospect Nick Gordon at the MLB level. -- Wildstein

Record: 58-72

Week 20 ranking: 23

Jacob deGrom's Cy Young case keeps getting stronger. He has a hefty lead in ERA (in the NL and in MLB), but his record always comes up -- he's 8-8 this season. No starting pitcher has ever won a Cy Young award with a losing record. The fewest wins by any starting pitcher to win the award is 13, by Fernando Valenzuela in a strike-shortened 1981 season and Felix Hernandez in 2010. But the bigger item is the team's record when he starts, just 11-15. The worst team winning percentage in a pitcher's starts for a Cy Young winner was .500 for Hernandez in 2010. -- Langs

Record: 60-70

Week 20 ranking: 24

Kendrys Morales has been red-hot over the past few weeks. Since Aug. 15, Morales leads baseball in hitting with a .486 batting average and eight home runs. From Aug. 19 through Sunday, Morales slugged homers in seven straight games, besting the franchise record for consecutive games with a home run. (José Cruz Jr. homered in six straight in 2001.) Morales' power surge helped push Toronto to its first five-game winning streak of the season. -- McCarthy

Record: 58-74

Week 20 ranking: 21

The Rangers started last week on a rough note, getting shut out by the Athletics in back-to-back games, just the fourth time in franchise history that has happened. That brought their losing streak against the A's up to six games before they snapped it on Wednesday. The Rangers are 23-34 (.404) against the AL West this season, on pace to be their worst divisional record since 2002 (20-38). -- Nitzberg

Record: 56-75

Week 20 ranking: 22

Joey Votto made his first trip to the disabled list since 2014, and it has been that kind of season for the Reds. Overall, it has been a disappointing season for Votto, especially in the power department, where he's posting the lowest isolated power rate of his career. After three straight seasons of 29 or more homers, he's struggling to reach half that total this year. -- Wildstein

Record: 53-78

Week 20 ranking: 26

After stumbling through a 2-4 homestand, the Tigers head out on a nine-game road trip. Detroit has had very little success away from home this season, going 19-44 (.302), with only the Orioles posting a worse road record this season. The Tigers are on pace to have their fifth-worst road record in franchise history and worst since their dreadful 2003 season, when they were 20-61 away from home. -- Nitzberg

Record: 51-79

Week 20 ranking: 27

After Tuesday's rain-shortened debut cost him a shot of giving White Sox fans an extended taste of what they've been anticipating since he came over in the Chris Sale trade, the Michael Kopech era got a more proper relaunch in Detroit on Sunday. The highly touted prospect earned his first win while showing off high-90s heat and 20 mph separation with his slider. The White Sox might be able to deal a few shutdown starts down the stretch to end the year on a high note if he and Carlos Rodon, one of the AL's best starters the past couple of months, perform well. -- Kahrl

Record: 50-83

Week 20 ranking: 25

Despite trading Brad Hand and Adam Cimber just before the second half, the Padres have had one of the best bullpens in baseball since the All-Star break. San Diego's relievers have a 3.25 ERA since the break, second best in the NL and third best in the majors. Their 11.4 K/9 leads the majors since the break. -- Nitzberg

Record: 53-79

Week 20 ranking: 28

Wei-Yin Chen is having a superb month for the Marlins. After struggling to a 3-8 record with a 5.86 ERA through 17 starts, over four starts this month Chen has a 1.54 ERA and wins over the Cardinals and Braves. In his most recent outing, he struck out double-digit batters for the first time since May 11, 2016. Chen will be on the books to make $20 million next season, so the Marlins may want to test the waiver trade market while Chen is surging. -- McCarthy

Record: 37-94

Week 20 ranking: 29

The Orioles lost eight straight as they remain on pace to deliver a win percentage under .300 and more than 110 losses. Dylan Bundy worked through another rough stretch this month, posting three straight games in which he's allowed at least seven runs, the second time this season that the young starter ran into that kind of trouble. Bundy is just the fifth pitcher since 1920 to allow seven runs in three consecutive starts twice in the same season. -- McCarthy

Record: 40-91

Week 20 ranking: 30

It has been a season to forget in Kansas City, as the Royals are easily on pace for the worst record in franchise history. Their loss on Wednesday dropped them to 51 games under .500, tying the worst mark in franchise history (and they broke it Thursday). Taking that Wednesday loss was Jakob Junis, who lost an August game for the first time in his career. Although Junis' 6-12 record is largely due to his 4.70 ERA this season, he's also received poor run support, getting the third-fewest runs per start in the majors this season. -- Nitzberg