Houston leads the AL West by 11 games and Washington is up by 8 1/2 games in the NL East, which could leave the other teams in those divisions fighting for wild-card spots even with four months of the season remaining.

Last season, the baseball-loving world was deprived of the drama of a pennant race. By Sept. 1, the Cubs, Nationals and Rangers had realistically sealed up their respective divisions. The Indians' lead in the AL Central never dipped below 4 1/2 games that month, and the Dodgers maintained at least a 4-game lead over the Giants in the NL West for the final three weeks of the season. The only division lead that changed hands at any point in September was the AL East’s, but even there the Red Sox moved ahead of the Blue Jays on Sept. 7 and never looked back.

Things look more promising this season, as four of the races—the AL East (Yankees over Red Sox by three games), AL Central (Twins over Indians by one game), NL Central (Brewers over Cubs by 1 1/2 games) and NL West (Rockies over Dodgers by one-half game—are tight. Yet that still leaves two that, barring something unlikely happening, may have already been decided.

Heading into play on Wednesday, the Astros hold an 11-game advantage in the AL West, while the Nationals are 8 1/2 games clear of their nearest competitor in the NL East. Since divisional play began in 1969, there have been 20 instances of teams possessing a 7-game divisional lead on May 31. Only two of those teams—the 1969 Cubs and 2014 Giants—failed to win their divisions. San Francisco, of course, nabbed a wild-card spot and rode that—as well as the left arm of Madison Bumgarner—all the way to a World Series championship. That leaves the famously snakebitten '69 Cub, who still led the NL East by 8 1/2 games as late as Aug. 19, as the only team to have such a big advantage and fail to close the deal. Houston and Washington, then, certainly have history on their side.

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The news is even better for the Astros, whose 11 1/2-game lead is the second-largest divisional advantage at this point of the season in MLB history. The record holder, the 2001 Mariners, were up 14 games in the AL West on the final day of May and ended up winning the division by that same spread while going 116-46, tying the major league's regular season record for wins. Houston is currently on pace to win 112 games and is the fifth team in MLB history with a double-digit game lead heading into June. The previous four teams to do so—the 1971 Giants, '99 Indians and 2007 Red Sox, in addition to the record-setting Mariners—all took home the division crown, with the latter three all winning at least 96 games. In other words, don't expect the Astros to be seriously challenged this summer as they head toward their first division title since 2001.

The Nationals are on solid ground as well as they chase their second straight NL East crown and their fourth since 2012. Every team that started June with a lead as big as Washington's 8 1/2-game edge went on to win its division. (If you're curious, the 1969 Cubs led the NL East by 7 1/2 games on June 1). The 2001 Phillies led the updated version of the NL East by eight games at the start of June but played .473-ball the rest of the season to finish two games behind the Braves. The 2014 Giants were up seven games on the Dodgers after a 20-9 May, but went three games under .500 the rest of the season. One month later that wouldn’t matter, but it did result in the Dodgers winning the NL West going away.

Our discussion to this point, however, has focused wholly on the past. That ignores the ingredients that have made these specific teams capable of building such large leads over the first two months of the season, and how they compare with the rest of the teams in their respective divisions. After all, these teams do not operate in a vacuum. To determine how likely it is that either the Astros or the Nationals lose their divisional leads over the next four months, we have to view them in their 2017 context. This is where those remaining teams in the AL West and NL East truly start to look like also-rans.

First, of course, is the talent. The Nats have the early favorite for NL MVP in Bryce Harper and the reigning NL Cy Young Award winner in Max Scherzer. The Astros have a pair of early MVP candidates in Jose Altuve and Carlos Correa and a leading Cy Young hopeful in Dallas Keuchel, the 2015 winner. Then there are the numbers. Houston leads the American League in runs, hits, batting average, on-base percentage and slugging percentage, as well as ERA and strikeouts. Washington is tops in the NL in all three slash stats as well as runs scored and home runs. There is one advanced stat that most be the most revealing of their dominance, though: weighted on-base average, which views home runs as batter than triples, triples better than doubles and so on. According to that metric, the Nats are first in the majors at .345 and the 'Stros are second at .341.

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After the Nationals, the next-best wOBA in the NL East belongs to the Mets, which check in at .320, good for 13th in the majors, but 25 points behind the Nats. The Braves and the Marlins are right behind them, while the Phillies .307 wOBA ranks 25th. The Astros, meanwhile, are clear of their next-closest AL West team by 26 points. The A’s rank 19th in the majors with a .315 wOBA. The Rangers and the Mariners follow closely behind the A’s, while the Angels are 27th with a wOBA of .301. That number is going to be a whole lot uglier by time he returns from his DL stint for a torn thumb ligament.

This is a little harder to compare historically, because there’s no way to drill down to wOBA on a specific date. We can, however, look at end-of-season wOBA and, again, the Astros and Nationals compare quite well to their predecessors who won their divisions going away.

Among the 17 previous division winners that had leads of at least seven games on May 31, the 1999 Indians produced the widest spread in wOBA between themselves and the next-highest team in their division. That year’s Indians, led by Roberto Alomar, Kenny Lofton, Manny Ramirez and Jim Thome, compiled a .367 wOBA. The next best mark in the AL Central belonged to the Royals, at .342. The only other team in our group with a double-digit wOBA lead was the 1993 Phillies, which were 15 points better than that year’s Cardinals in the NL East.

Baseball is proving Yogi Berra right yet again. It has gotten late early for the Rangers, Mariners, A’s, Angels, Mets, Marlins, Braves and Phillies. There may be four months and more than 100 games left in the season, but one of those eight teams would have to make history to prevent the Astros or Nationals from winning their divisions.