The Cardinals completed a major trade that landed them first baseman Paul Goldschmidt from the Arizona Diamondbacks on Wednesday in exchange for catcher Carson Kelly, pitcher Luke Weaver, infielder Andy Young, and a draft pick:

Here are some things you need to know about the week's latest eye-catching hot stove deal.

Goldschmidt gives the Cardinals a big boost

Goldschmidt, 31, is entering the final year of his team control. He is, without a doubt, one of the best first basemen in baseball -- and has been throughout his career. To wit, he recovered from a slow start last season to hit .290/.389/.533 (139 OPS+) with 33 home runs. For his career, he's hit .297/.398/.532 (145 OPS+) with 209 home runs. Consistent, huh?

That's the obvious benefit of slotting Goldschmidt into the middle of the order, of course, but there are other effects at play, too.

By adding Goldschmidt to the roster, the Cardinals can now shift Matt Carpenter back across the diamond to third base, effectively upgrading their production there and improving their bench by relegating Jedd Gyorko to reserve duty. The Cardinals could also opt to trade Gyorko, or insert him at second base in place of Kolten Wong. Whatever St. Louis decides to to do there, the team can do it because Goldschmidt is around.

Don't overlook that the Cardinals are also taking away from the team that could've conceivably competed for a wild-card slot alongside them in 2019, either. The Cardinals finished with six more wins than the Diamondbacks, sure, but in terms of run differential, the clubs ranked 12th and 13th in baseball (third- and fourth-best among non-playoff teams).

The D-Backs are buying low on young talent

Kelly and Weaver are the key pieces of the return for the Diamondbacks. Both could see their stocks improve greatly within a year.

Kelly has taken well to catching since moving there from third base early in his career. His athleticism, strong arm, and leadership qualities should make him an asset defensively. He hasn't hit well in limited exposure to big-league pitching (.154/.227/.188 in 63 plate appearances), but his minor-league performance and scouting reports suggest he could provide an average stick. Even if he doesn't, his mitt alone should enable him to start games as soon as this year.

Weaver is a skinny right-hander who started 25 times last season and ended up with a 78 ERA+ and a 2.24 strikeout-to-walk ratio. He's primarily a two-pitch pitcher, leaning on his mid-90s fastball and a changeup that used to be held in high regard. Batters hit .271 off the pitch last season, however, and he's been worse against lefties for his career.

Each became available because the Cardinals had other internal options. Yadier Molina has become the definitive Cardinals backstop, but they also have top prospect Andrew Knizner on the rise. Weaver, meanwhile, no longer appeared to have a grip on a rotation spot. The Cardinals appear to have sufficient depth in that regard, too, with Alex Reyes, Austin Gomber, and Daniel Poncedeleon ready to step in if need be.

Young, for his part, is considered more of an organizational player. He did not appear in MLB.com's top 30 prospect list for the Cardinals -- that despite posting an .858 OPS between High- and Double-A last season.

The D-Backs are rebuilding

As for the Diamondbacks, this is further confirmation that they intend to rebuild. Arizona saw Patrick Corbin leave for the Washington Nationals on Tuesday, and stands to lose A.J. Pollock to the highest bidder in the coming days. The Diamondbacks are also expected to try moving Zack Greinke before the winter is out.

Earlier in the offseason, we covered some other players Arizona could look to move. There's enough talent there that it shouldn't be a surprise if GM Mike Hazen makes a few more deals between now and opening day.