Luis Castillo seemed destined to be traded to the New York Yankees or Los Angeles Dodgers. Almost every rumor indicated that one of the big market teams would get a deal done for the Cincinnati Reds ace. Instead, the Seattle Mariners swooped in and landed Castillo. But was it a good trade for Seattle? Let's breakdown this blockbuster deal between the Mariners and Reds.

Grading Mariners-Reds Luis Castillo trade deadline deal

What the Reds gave up

Luis Castillo had been the Reds ace for a few years. He'd been a member of the team since 2017, but officially emerged as a star in 2019 when he struck out 226 batters and posted a 3.40 ERA. Castillo has posted an ERA under 4 in each year since, but is arguably in the midst of his best season right now.

Castillo currently owns a 2.86 ERA with a 1.07 WHIP. He's holding opposing hitters to a .201 batting average and has 90 strikeouts on the season. As a result, Castillo was selected to the All-Star game.

He features a versatile pitch arsenal with an absolutely filthy change-up. He also reaches the high 90's with his fastball. 

He is an incredibly difficult pitcher to square up. The Reds loved what they had in Castillo, but are in a rebuilding phase so trading him was the best course of action.

What the Mariners gave up

The Mariners sent a haul back to Cincinnati. MLB Network's Jon Morosi reported that Seattle sent prospects Noelvi Marte, Levi Stoudt, Andrew Moore, and Edwin Arroyo to the Reds. Marte was the Reds No. 1 prospect, while Arroyo was No. 3 and Stoudt was No. 5.

This deal likely removes the Mariners from Juan Soto consideration. They would have needed to send the Nationals a package highlighted by Noelvi Marte, who is one of the better prospects in all of baseball. But the Mariners clearly believe in Luis Castillo.

Marte, a 6'1 shortstop, has impressive tools. He has plenty of natural pop in his bat to go along with a quality hit tool. Many expect him to develop into an All-Star caliber offensive player at the big league level. He is a candidate to move to third base at some point, but he isn't a bad defender at shortstop.

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But his offense is what stands out.

Arroyo, also a shortstop, is a plus defender with impressive offensive ability as well. Stoudt is a left-handed pitcher who features a mid-high 90's fastball and a tremendous splitter. Andrew Moore is a right-handed pitcher who offers high velocity but needs to work on control.

Grading the trade

So who won the trade?

I would say both teams came away with wins in this deal. On paper, the Reds got a loaded return package for Castillo. It is possible that Seattle only has the right-hander for a year and a half since Castillo will be a free agent following next season.

The Reds got 3 of the Mariners top 5 prospects which fits perfectly into their rebuilding strategy.

With all of that being said, I don't blame Seattle for going all in on Luis Castillo. The Mariners are desperate to snap their MLB leading playoff drought. This is a franchise that couldn't afford to stand pat. They needed to swing a big deal and they got a star pitcher.

Did they overpay? Maybe. But they had to out-bid teams such as the Yankees and Dodgers to acquire the right-handed ace. And when you haven't made the playoffs in 20-plus years, overpaying on the trade block isn't always a bad thing.

Reds trade grade: A

Mariners trade grade: A