The Astros probably could not be better positioned to win a second straight World Series than right now. In its simplest terms, that's what the trade for Pirates right-hander Gerrit Cole on Saturday means.
This is about two things.
First, executives of championship teams always debate how much to tinker with a formula that has just worked beautifully. Why fix what's not broken?
On the other hand, there's this bit of wisdom from Hall of Fame manager Tony La Russa: "You've got to change the group dynamics every season because they're going to change anyway in a whole bunch of ways."

He meant that whatever magic a team had in one season can't be captured two years in a row, as age, injury, approaching free agency, etc., change things.
Besides that, human nature is what it is. The Astros won two Game 7's in 2017 and played some of the craziest games in postseason history. After all that, the view from the mountaintop surely changes the perspective, if only slightly.
That said, the Astros loved their team before this trade and believe they've got at least a two-year window to win again. Two years also happens to be how long Jose Altuve and Justin Verlander -- and now Cole -- are under contract.

This trade is a shock to the status quo. And while general manager Jeff Luhnow likes his team's talent, approach, work ethic, energy, you name it, some aspects of it give him pause.
From the outside, his team seemed set for 2018 with a great lineup, deep rotation and improved bullpen. Inside the offices at Minute Maid Park, Luhnow felt less certain. Dallas Keuchel and Lance McCullers both spent time on the disabled list in 2017 and were injured at the end of '16. Maybe that rotation wasn't as deep as some thought.
There's also the longer view. Keuchel and Charlie Morton will be free agents after the 2018 season, and Keuchel's hiring of agent Scott Boras means he's almost certain to test the free-agent market. He has previously rejected overtures about a long-term deal.
So if Luhnow could add Cole for two seasons, he could shape a super rotation for 2018 and a really good one for 2019. To have Verlander, Cole and Keuchel lined up in the first three spots gives the Astros a group as good as almost any. And there's quality depth in Morton, McCullers, Brad Peacock and Collin McHugh.
In addition, Luhnow made outfielder Kyle Tucker and right-hander Forrest Whitley, who is MLB Pipeline's 36th-ranked prospect and on track to pitch in the majors in 2018, untouchable. In the end, Luhnow sent the Pirates right-handers Joe Musgrove and Michael Feliz, outfielder Jason Martin and third baseman Colin Moran.
What are the Astros getting in Cole? In 127 career starts, the 27-year-old right-hander has a 3.50 ERA and 1.217 WHIP. His fastball was clocked at 96 mph in 2017, but his slider might be his best pitch. He could benefit from the Astros data bank and insistence that pitchers build their game plans around their best pitch instead of the traditional belief in first establishing the fastball.

That philosophy saw Morton throw his curveball a career-high 28.4 percent of the time in 2017 and was never more evident than Game 7 of the American League Championship Series, when McCullers ended a victory over the Yankees with 24 straight curves. By contrast, Cole threw his slider just 17.2 percent of the time in '17.
Before making this trade, Luhnow considered several other rotation options, including free agents Yu Darvish and Jacob Arrieta as well as Tampa Bay trade candidate Chris Archer. In the end, he decided that two years of Cole gives the Astros their best chance to win another World Series, while maintaining salary flexibility for 2019 and beyond. There may not be any perfect fits, but this one is close.