The Astros, who were a trendy pick to make the playoffs this year, surpassed all expectations and began to run away with the American League West, opening up a 10-game lead by May 16 and eventually joining the Dodgers as baseball's only 60-game winners in the first half.
Behind the deepest offense in baseball, Houston overcame a rash of injuries to its starting pitchers by scoring runs in bunches, especially on the road. The Astros were historically good away from Minute Maid Park (33-11) and had a string of come-from-behind wins that proved no lead was safe against their offense.
With a 16 1/2-game lead in the division entering in the second half -- and a pitching staff that's increasingly on the mend -- Houston will face the challenge of trying to stay focused heading into the thick of a pennant race it figures to dominate.
:: 2017 Midterm Report: Complete coverage ::
What went right 
The offseason additions of veterans Carlos Beltran, Brian McCann and Josh Reddick were terrific. Beltran didn't put up big numbers, but the 40-year-old's veteran presence was big in the clubhouse. Reddick was having a career year offensively in the first half, and McCann was as good as advertised. Carlos Correa and outfielder George Springer blossomed into All-Stars, and second baseman Jose Altuve continued to be one of the most elite hitters in the league. First baseman Yuli Gurriel and outfielder Jake Marisnick became impact hitters. Super-utility player Marwin Gonzalez took his game to All-Star levels in a career first half, though he didn't make the team. Reliever Chris Devenski, no longer an unknown commodity, emerged as one of the most feared relievers in the league. Mike Fiers and Brad Peacock were steady hands in the rotation.
What went wrong 
At one point, the Astros' top four starting pitchers entering Spring Training were all on the disabled list at the same time -- ace Dallas Keuchel, Lance McCullers, Charlie Morton and Collin McHugh, who missed the entire first half. When healthy, Keuchel and McCullers were dominant, and Morton displayed some heretofore unseen velocity. The injuries to the starters took a toll on the bullpen, which absorbed a heavy workload because the starters weren't pitching deep into games. Rookie pitcher David Paulino was suspended 80 games for testing positive for a performance-enhancing drug.
What we learned 
The Astros are good enough to win the World Series, thanks to the deepest lineup in baseball. Even when they had so many key starters on the disabled list, they didn't skip a beat because they were so prolific and relentless on offense. They have elite starting pitching when Keuchel and McCullers are healthy, which means a Houston team at full strength will be a difficult matchup for anyone in October.
First half top everyday player  
Springer. And that's with Correa and Altuve having the kind of first halves that could earn them getting AL MVP Award votes. But Springer's power surge and the way he set the tone at the top of the batting order was as much a key to the Astros' offensive success as anyone. Honestly, any of the three would be a solid pick.
First half top pitcher 
Devenski. Yes, Keuchel and McCullers were also All-Stars and could get AL Cy Young votes, but both battled injuries. Thus, Devenski impacted more games because of his ability to come into the game in high-leverage situations and pitch multiple innings, and pitch them well.
First half top rookie 
Gurriel. He turned 33 during the season, but was still considered a rookie after Houston signed him to a five-year, $47.5 million deal following a decorated career in Cuba. Outside of a poor May in which he hit .200, Gurriel swung a great bat, especially for someone hitting near the bottom of the order.