The Reds traded right-handed ace Luis Castillo to the Mariners on Friday in exchange for a package of top prospects.

Castillo, the top starting pitcher available on the market before Tuesday’s MLB trade deadline, will bolster the rotation of a Mariners team hoping to make its first playoff appearance in two decades. By sending their double All-Star to the AL West, the Reds (38-61, last in the NL Central) store prospects for their reconstruction.

In that sense, both teams got what they wanted, although it’s clear the Mariners made the loudest noise. We’ll now see if the deal will help lead to a playoff run.

In the meantime, here’s what you need to know about trading:

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Luis Castillo Business Details

  • Sailors get: HRP Luis Castillo
  • Reds get: minor league SS Noelvi Marte and Edwin Arroyo; and minir league RHPs Levi Stoudt and Andrew Moore

As first reported by ESPN Jeff Passan (and confirmed by the Seattle Times’ Ryan Divich), the Mariners parted with four prospects in exchange for the Reds’ ace. The group includes the top 100 prospects in Marte (No. 18) and Arroyo (No. 93).

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Luis Castillo contract details

Castillo earns $7.35 million in 2022 and is eligible for salary arbitration in 2023. He can become a free agent after season 23.

2022 2023 2024
Luis Castillo $8.5 million ARB 3 FA

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What do the Mariners get for Luis Castillo?

The Mariners get the best starting pitcher in the trade, making a rotation previously led by playoff-caliber Robbie Ray and Logan Gilbert.

The move is a big splash; Seattle now has Castillo on hand for what it hopes will be a strong end to the regular season. The Mariners are 54-46 and 11 games behind the Astros in the AL West, but currently own the league’s second wild card. The team is looking for its first playoff appearance since losing the 2001 ALCS to the Yankees.

Castillo is in the midst of a second All-Star season. He compiled a 2.86 ERA in 14 starts (4-4 record) for Cincinnati, with 63 hits allowed, 30 runs (27 earned) and seven homers allowed.

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What do the Reds get in Mariners prospects?

Cincinnati did very well in the trade, getting four prospects to help rebuild the team.

Headlining that group is Marte, the No. 18 minor league prospect and seventh-ranked shortstop. He has a .275/.363/.462 slant line in single-A highball in 2022, including 62 runs, 94 hits and 15 homers coming in Friday.

The other top-100 player involved in the trade is Arroyo, the Mariners’ third-best prospect and 93rd overall player in the minor leagues. The 18-year-old has a .316/.385/.514 slant line with 76 runs, 115 hits and 13 Single-A low home runs.

The deal also includes two pitchers in Stoudt (Seattle’s No. 5 prospect) and Moore, who isn’t listed as a team prospect according to MLB Pipeline. Stoudt has a 5.28 Double-A ERA in 2022, allowing 92 hits and 13 homers while striking out 82.