The Houston Astros have been the year's most surprising Major League Baseball team. They began the season with the expectations that they would perform marginally better than their 72-90 record of the previous year: Maybe, if the team got lucky in 2015, they'd win about 50 percent of their games.

But defying all oddsmakers' predictions, the team finished the first half of the season second only to the Kansas City Royals for the most wins in the American League. They will go to the playoffs, and they will hold their own in the playoffs; there is no doubt. What remains to be seen is how far they will go.

But before we look at how far they might go in the future, we need to understand how far they've already come. The last ten years have been cruel to the Astros. Coming off of a 2005 World Series appearance, the Astros lost their chance to play in the 2006 playoffs in the last game of the season. The next year, star slugger Jeff Bagwell and Hall of Famer Craig Biggio — whose numbers have since been retired by the club — retired, and the team began its steep decline.

The team barely missed the playoffs in 2008, in large part due to a crucial series with the Chicago Cubs. Although the series was scheduled to be played at the Astros' stadium, Minute Maid Park, MLB's then-Commissioner Bud Selig moved it to Milwaukee, a/k/a "North Chicago," after Hurricane Ike made landfall in the Houston area. Cubs pitcher Carlos Zambrano benefited so much from the hometown environment that he threw a no-hitter against the Astros, who still played as the home team. But the team's record in 2009 was almost flipped, at 74-88. Meanwhile, in 2010, the team traded lineup lynchpin Lance Berkman to the universally hated New York Yankees and finished the year with a sub-.500 record. And during the off-season, then-owner Drayton McLane announced that he planned to sell the team.

McLane's announcement propelled the team to lose more than 100 games for the first time in 2011, after which he sold the team to its current owner. Jim Crane. The team didn't just change owners — it also changed logos (from an open five-pointed star to a circular shield with an H superimposed on a star) and color schemes (from brick-red, sand and black to navy blue, orange and white).

And most controversially, it changed leagues, moving from the National League to the American League as a way for Selig to impose his arbitrary desire to have each league, and their three divisions, have an equal number of teams. The move was not only controversial because of history — the Astros had played their first 50 years in the National League — but also because the team would have to place a designated hitter, who bats in the pitcher's place, in its American League lineups (the National League doesn't use the designated hitter at its home parks).

For many fans, this change was the hardest to stomach: Only one other team, Selig's own Milwaukee Brewers, which he owned before becoming Commissioner, had switched leagues before. But it had done so voluntarily, while Selig required the Astros to switch leagues as a prerequisite to its sale to Jim Crane. And so Selig became a tyrant in the hearts of many Astros fans.

But the move hasn't been a death knell for the team — if anything, it's been a rebirth. But success has come slowly.

Crane's first seasons with the club were challenging. He hired Jeff Luhnow to be the team's general manager; Luhnow had formerly served as GM for the St. Louis Cardinals, the Astros' most heated rivals. Luhnow's data-driven approach helped the team acquire a boatload of prospects and make their minor league teams the best in baseball.

But promises of progress don't always add up, and first-round draft picks, in particular, have a frustrating habit of not playing to their potential. And the Astros played so badly in the first two seasons of Crane's ownership — finishing the 2012 and 2013 seasons with more losses than the season before it (55-107 and 51-111, respectively) — that they picked the very first player in the next seasons' draft.

The team rolled out a cast of nobodies, had-beens and would-never-bes at the same time it was unable to televise its games to more than 40 percent of the city. So calling these seasons challenging is, again, something of an understatement. But the fans who stuck around saw flashes of progress: Jose Altuve and Dallas Keuchel had breakout seasons last year — Altuve won a batting title, and Keuchel won a Gold Glove Award — and Chris Carter, whose swing is so smooth that grown men swoon when they see it, hit 29 home runs in 2013 and 37 the next year. So even though the Astros were still largely expected to play below .500 this season, fans expected them to make good on their promises soon.

And against all odds, the Astros have. The Astros are not only playing baseball with a winning record, but they're in first place in their division, and they have the most wins in the American League!

Their starting pitching is far and away more consistent than last year. Dallas Keuchel has secured his spot as the Astros' ace, not with overpowering speed, but with overpowering control. He pinpoints his pitches with such accuracy that he gets hitters to hit more pitches for ground balls than almost any other pitcher in the majors — a quality highly valued by Astros brass. Collin McHugh, a pitcher who's similarly focused on control, is another solid pitcher; Scott Feldman, when healthy, provides veteran presence and an old, reliable arm to the rotation. The recent additions of Vince Velazquez and Lance McCullers, the team's resident fireballer, have also helped the Astros' starting pitching improve dramatically.

Crucially, the Astros' relief pitching has improved substantially from last year; the low-profile additions of slinky sidearm relievers Luke Gregerson and Pat Neshek, along with the waiver-wire pickup of Will Harris, have made the bullpen more likely to blow up the strike zone, not the game.

The team's hitting, of course, has seen the most notable improvement thus far. The team holds the unusual distinction of leading the majors in home runs, stolen bases, and strikeouts, showing the Astros' decision to rely on power hitting and speed for run support. No Astro has a batting average above .300, and two — sluggers Chris Carter and Luis Valbuena, the latter of whom has the second-most home runs in the American League — are hitting below .200, the infamous "Mendoza Line," named after similarly infamous Mario Mendoza and his seeming inability to never, ever hit above .200 in his career. Meanwhile, five regular players have ten or more home runs, and three have ten or more stolen bases.

The team added a glut of players — Valbuena, Evan Gattis, Colby Rasmus among them — in the off-season to revitalize its previously anemic lineup, and the team is more alive than ever: Rasmus has ten home runs, and Gattis is tied with home-grown Astros star George Springer; each has thirteen home runs. Perhaps the most welcome addition to this year's Astros lineup, however — the one that shows they are a force to be reckoned with — is the team's star shortstop, Carlos Correa. In less than a month, Correa has already invited talk of being an American League All-Star, is projected to hit about 30 home runs on the year, and is indisputably the best shortstop in the major leagues. Not bad for a 20-year-old!

And besides Correa, the Astros' farm system has plenty of players ready to make their mark on the major leagues. Mark Appel, a starting pitcher picked first in the draft by the team in 2013, is the most notable example.

The long and short of it is: The Astros are here to stay. They will be so good this season that they will make it to the playoffs. The team finally appears to have its puzzle pieces in place; their ground ball-based pitching rotation is one of the best in the league, and their consistent relief pitching helps them; their hitting, while unconventional, remains successful.

But more important than numbers is the way they're playing. The Houston Astros are playing with a vengeance, like they want to erase the painful memories of the last ten years. Soon, an Astro will walk down the street and people will say, "There goes the defending World Series champion." Until then, it's in Major League Baseball's best interest to watch out.

Eli Winter lives in Houston.

Bookmark Gray Matters. It will go to the playoffs.

