NATIONAL HARBOR, Md. -- The Boston Red Sox pulled off a blockbuster trade Tuesday, nabbing Chris Sale from the Chicago White Sox for a four-prospect package headed by Yoan Moncada and establishing themselves as the favorites to win the American League pennant.

In Sale, the Red Sox acquired one of the five best pitchers on Earth. Since becoming a full-time major league starting pitcher in 2012, Sale ranks fourth among all starting pitchers in strikeout rate, 10th (lowest) in walk rate, third in park-adjusted ERA, second in park-adjusted fielding-independent pitching, and fourth in Wins Above Replacement, trailing only Clayton Kershaw, Max Scherzer and David Price. Despite carrying a rail-thin, 6-foot-6, 180-pound frame and pitching from a three-quarter angle that evokes winces, he's defied critics who predicted injuries for him, averaging 203 innings per season.

He's not some rent-a-vet either. Just 27 years old, Sale is right in his prime, producing elite results in 2016 with his deadly fastball-slider combination that were on par with the very best. Though his strikeout rate (25.7 percent in 2016 vs. 32.1 percent in 2015) and average fastball velocity (93.6 mph in 2016 vs. 95.6 mph in 2015) both dropped last season, that was by design, as Sale sought to go deeper into games by changing speeds and inducing quicker outs.

The Red Sox have a pitcher in the prime of an elite career in the recently acquired Chris Sale. USATSI

The Red Sox also gain control over Sale's rights through the 2019 season, with those three years costing just $38 million. Last offseason, David Price signed a seven-year contract with Boston for $31 million per year. Sale is two and a half years younger now than Price was when he signed that deal, with a similarly excellent track record. It's not unreasonable to peg his value on the open market at somewhere approaching $35 million a year. That gap between Sale's salary and real-life value made him worthy of a huge haul in trade.

And the White Sox got a pretty strong haul. In Moncada, they snagged the top prospect in the Red Sox organization, and one of the best in baseball (No. 3 in all of baseball coming into the 2016 season, according to Baseball America). Just 21 years old, Moncada's swing has already been pegged as one of the sweetest in the game, reminiscent of Robinson Cano's. In 187 minor league games, Moncada has hit .287/.395/.480, pairing excellent power with precocious plate discipline. He's yet to dazzle as a second baseman, but scouts think he has the athleticism to handle that position capably, with his bat remaining his calling card. Moncada made his major league debut in 2016, and could become a linchpin of the White Sox lineup for the next six seasons.

The second significant piece for Chicago is Michael Kopech. The 20-year-old right-hander ranked as Baseball America's No. 89 prospect coming into the 2016 campaign. He's since raised his stock, whiffing 38 percent of the batters he faced at two levels of Class A ball, with a 2.08 ERA. His resume isn't perfect: Demerits include sometimes iffy control (he walked 33 batters in 56 1/3 innings in 2016), and a broken hand resulting from a fight with a teammate that limited him to 12 starts last season. Still, Kopech's fastball can touch triple digits, his slider and change-up both grade as potential plus offerings, and he's widely regarded as one of the best pitching prospects in the game. Even with the other two prospects in the trade (22-year-old right-hander Victor Diaz and 20-year-old outfielder Luis Basabe) regarded as longer-odds bets to make a major mark in the big leagues, Moncada and Kopech could become impact players on the South Side.

It's still a trade that makes tons of sense for the Red Sox. Go through the annals of baseball history, and you'll find far more examples of blockbuster trades tipping in favor of the team that acquired the superstar rather than the club that got the package of prospects (think Roy Halladay for Travis d'Arnaud, Kyle Drabek, and Michael Taylor). Boston rolled to an AL East title last season thanks to a power-packed lineup led by Mookie Betts, Xander Bogaerts, David Ortiz, Dustin Pedroia and Jackie Bradley Jr., only to come up short in the playoffs. The missing ingredient in last season's Red Sox run was pitching depth: The back of the rotation was often suspect, the bullpen even more so.

The Red Sox also made an under-the-radar move for bullpen depth by adding Tyler Thornburg. USATSI

In a span of 24 hours, the BoSox addressed both those needs. Sale will team with David Price and 2016 Cy Young winner Rick Porcello to form one of the most potent pitching trios in the league, while creating a scenario that gives at least four candidates (Drew Pomeranz, Eduardo Rodriguez, Steven Wright and Clay Buchholz) a shot at the other two spots. Meanwhile, Boston picked up Tyler Thornburg from the Brewers Tuesday morning, landing a lights-out right-handed reliever who punched out 90 batters in 67 innings last season, with a 2.15 ERA. Thornburg will team with a hopefully healthier Craig Kimbrel (he was limited by knee problems in 2016) to form a strong one-two punch at the back of the pen. A summer 2017 return by fellow righty Carson Smith (who had Tommy John surgery in May), combined with multi-inning relief work from Joe Kelly and contributions from the two pitchers who don't crack the rotation, could give Boston one of its best and deepest bullpens in a while.

All of this is right out of the Dave Dombrowski playbook. Few executives in the game put more stock in frontline starting pitching than Dombrowski, and perhaps no exec is so willing to sacrifice marquee prospects (and/or big money) to get those elusive aces. Thanks to a combination of graduations to the majors and splashy trades, the Red Sox farm system is far, far thinner than it was in the summer of 2015, when the organization tapped Dombrowski to head up baseball ops.

If Boston wins another World Series next year, no one will give a damn. Given how successful the Red Sox have been at filling their biggest holes, they'll now have a good chance to make that happen. With four months to go until Opening Day and one more move to acquire a David Ortiz replacement almost certainly on the way, the Red Sox are the early front-runners in the American League.