The White Sox announced they have acquired Yoan Moncada, Michael Kopech, Luis Alexander Basabe and Victor Diaz in exchange for Sale.
Fox Sports' Ken Rosenthal initially reported the deal.
Bruce Levine of 670TheScore.com also reported the Red Sox will pay the $31.2 million remaining on Moncada's $63 million deal. Bob Nightengale of USA Today reported that the Red Sox refused to include Jackie Bradley Jr. in any trade talk.
Boston beat out the Washington Nationals, who tried "hard" to land the ace by offering top prospects, per Jon Heyman of Today's Knuckleball. Jorge Castillo of the Washington Post reported the Nationals weren't willing to give up Trea Turner and that the Red Sox's willingness to part with Moncada led to the swap.
Buster Olney of ESPN reported that a "popular theory in the industry" is that the White Sox pushed the Nationals to the brink of a deal to use as leverage to get the package they did from the Red Sox.
Ian Browne of RedSox.com and Pete Abraham of the Boston Globe provided comments from Sale on Wednesday:
Red Sox president of baseball operations Dave Dombrowski spoke with reporters on Tuesday, saying talks between the sides "accelerated" on Friday.
"Sale gives us a chance to win now...At this point, this gave us a really significant chance to win," Dombrowski said.
The White Sox seemed to be moving toward dealing Sale or Jose Quintana shortly before the trade deadline this past summer.
Heyman reported on July 22 Chicago began taking calls on the pair, though he added the White Sox hadn't "decided how seriously to shop their stars, and there's no certainty that either will be traded, as they love both pitchers."
Like most trade negotiations, the White Sox were waiting to get the best deal. It's not an unreasonable position for them to take, even as they appear headed for their fifth straight losing season, because Sale's contract is so team-friendly.
Recently retired Red Sox star David Ortiz is a fan of the move:
Sale, who is 27 years old, has one more guaranteed year on his deal at $12 million, with club options for 2018 and 2019 that total $26 million, per Baseball-Reference.com. His contract looks even better considering 43-year-old Bartolo Colon was among the top names of the available free-agent starters.
The White Sox have taken a short-term approach to fixing their roster, signing players such as Melky Cabrera and Jose Abreu and trading for Todd Frazier, yet it hasn't worked out. It's time for the franchise to start acquiring as many young, cost-controlled assets as possible to avoid a total collapse.
White Sox general manager Rick Hahn told reporters he thinks Moncada can play second or third base, "but at this point we'll have him playing second base" in the minors. Hahn added that the two sides had talked about Sale for over a year.
"If a team is interested in talented, controllable starting pitchers, we do have others," Hahn told reporters.
Meanwhile, the Red Sox get the top-of-the-rotation starter they needed. Dombrowski has not been shy about making deals to improve the team since taking over late in the 2015 season, acquiring Craig Kimbrel in a trade with the San Diego Padres and signing David Price last offseason.
Yet things did not work out for Boston's rotation in 2016, aside from Rick Porcello's breakout campaign. The Red Sox finished eighth in the majors with a 4.22 ERA from the starting rotation, though, so there was upside even before acquiring Sale.
It also helps that their offense led the league in most major offensive categories last season, including runs scored, doubles, total bases, average, on-base percentage and slugging percentage.
Sale is the horse Boston needs to get over the hump in October after a quick playoff exit last season.
Dombrowski has been making a lot of moves involving Boston's prospects, but it's such a rich farm system that he can get away with it and not leave the cupboard bare.
The White Sox could afford to move Sale because they still have Quintana to build a rotation around. This move will help them secure their future and start competing for a playoff spot for the first time since 2008.
Sale did everything in his power to make the White Sox a contender, finishing in the top six of AL Cy Young Award voting in each of the last five seasons. He's never had a chance to show off his stuff in October, but he will have an opportunity to change that with his new club.
It's never easy to give up multiple top-level prospects, but it's also rare when a true No. 1 starter who is under team control for more than two months becomes available. That made it easy for the Red Sox to make the call.