HOUSTON -- Three years have passed since the Astros and Dodgers executed a somewhat innocuous, under-the-radar midseason trade that today looms large. It involved a veteran reliever who was needed for the postseason stretch drive, and a young, raw, unproven hitter who had a chance to factor into the future of a franchise still on the rise.

The returns are in, and it's likely neither side would argue that the Astros, indisputably, won this one.

Astros president and general manager Jeff Luhnow sensed Yordan Alvarez had a decent chance to develop into a Major League hitter when he brokered a deal in 2016 with then-Dodgers GM Farhan Zaidi, who was seeking reinforcements for his playoff-bound club and was aggressive with his desire to acquire reliever Josh Fields.

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Luhnow was also discussing Fields with other interested teams, but Zaidi was persistent.

"The players we kept asking for, they kept saying, 'No, we can't do that, we can't do that,'" Luhnow recalled. "You always start kind of up our list and move down. Then, we got to the point where going any lower wasn't going to satisfy us. We were at an impasse."

But the day before the Trade Deadline, Luhnow remembered Alvarez, a teenager out of Cuba who, as an amateur free agent, had piqued the interest of several clubs, including the Astros. At that time, mid-June 2016, Alvarez ended up coming to an agreement with the Dodgers. Luhnow quickly put Alvarez out of his mind -- for about six weeks, that is, until the Dodgers came calling.

"Really, it wasn't until the day of the Deadline that I remembered the Dodgers had signed Alvarez, and I thought, 'Well, if we can't get a Minor League player that we're really excited about, why don't we just take a flier on this young guy that they just signed that I know we like?'" Luhnow said.

A few phone calls later, the deal was done. Fields to the Dodgers; Alvarez to the Astros.

Alvarez, who had not yet even received his signing bonus from the Dodgers, smiled at the memory of finding out he was dealt.

"I was surprised and a little worried," he said. "I didn't know what a trade was. I thought they might have been releasing me. I was really surprised, but when they explained it to me, I understood."

It's still early, but this one has a good chance to be added to that big list of The Most Lopsided Trades in Baseball History. Fields pitched for the Dodgers for three seasons and he was released during Spring Training this year. Alvarez is not only the runaway favorite to win American League Rookie of the Year Award, but he's hinting that he might find himself in the Most Valuable Player Award conversation for the next decade.

Alvarez was one of the top AL hitters from the day he debuted on June 9 through the remainder of the season, a stretch of 87 games. He ranked second in RBIs, third in on-base percentage and slugging and fourth in OPS. He set a franchise rookie record with 22 home runs, and he set a Major League record for RBIs in his first 45 games with 51, surpassing Ted Williams' mark of 47 in 1939.

Alvarez soared soon after he joined the organization. Luhnow would get regular reports from their academy in the Dominican Republic detailing Alvarez hitting the ball harder than anyone. When Alvarez came to Spring Training the next year, "There was a buzz in camp," Luhnow said. "All the coaches were talking about this kid that's crushing the ball."

Alvarez was invited to Major League camp this season, as a precursor to the likely scenario that he would be called up at some point during the regular season. He hit well during his time in big league camp, but ironically enough, the power wasn't there. He ended up with no home runs for the spring.

"It was Spring Training, so I was just warming up," Alvarez said. "I figured if they weren't going out there, then they would have to go out during the season. And they did."

A strong Triple-A start made the eventual callup inevitable. The Astros were confident he'd fit in well into their talent-laden lineup, but they could not have imagined how quickly he would adjust to Major League pitching. Luhnow likened Alvarez to future Hall of Famer Albert Pujols -- same calmness in the batter's box, with a similar ability to recognize pitches.

"You just knew if he got a pitch anywhere in his hitting zone he was going to destroy it," Luhnow said of Alvarez. "The fact that you can just see the pitchers notice how confident he is -- he doesn't even step out of the box. He's ready to hit right after he swings. Most hitters have to regroup. He just says, 'That one didn't work. Bring it on.' I think that kind of freaks out pitchers a little."

Alvarez will open the postseason with the Astros on Friday with the least amount of playing experience, but don’t expect that to translate to a lack of confidence. His teammates have assured him the playoffs are just like any other time of the year, “but with more fans and cameras.”

“I'm excited, but this is normal,” Alvarez said. “This is baseball. I'm going to just continue to do the same work as I did during the regular season and keep doing that.”