SEATTLE -- For years, Jerry Dipoto’s front office coveted Luis Castillo from afar, well before he reached the Majors and blossomed into one of the game’s elite workhorses. And on Saturday, the Mariners’ president of baseball operations and his staff locked up the two-time All-Star long term.

The club announced it has finalized a five-year contract extension that begins next season and runs through 2027. Both the club and player have contract options that could extend the deal through '28.

“I’m very happy that I am here,” Castillo said before Saturday's game against the Royals at Kauffman Stadium.

"Really good news. Outstanding," manager Scott Servais said. "I know Luis is very happy and the organization is very happy. Nobody is happier than the manager. He has been a great addition to our team and a great fit in the clubhouse."

Why did Castillo want to stay in Seattle long term?

“It’s the camaraderie that’s in here," he said. "I came here with the guys I knew from the Reds. I came here with an open mind and when I got here everybody was a tight group.”

Here are the details, according to sources:

• The deal is worth $108 million, with a vesting option that could take the deal to six years and $133 million, triggered for $25 million for 2028 if he pitches at least 180 innings in ‘27.

• Castillo received a $7 million signing bonus, and he’ll earn $10 million next season in what would’ve been his final year of eligibility for salary arbitration. Then, from 2024-27, he’ll earn $22.75 million per season.

• It includes a full no-trade clause for the first three years, and there are no player opt outs at any point during the deal.

• The club option is unique, and it basically gives the Mariners some health protection. It’s for one year and $5 million for 2028 and can only be exercised if Castillo undergoes surgery to repair his UCL (Tommy John surgery) and misses at least 130 days at any point from 2025-27. It’s essentially a safety net for the club should Castillo miss an extended period then return at an elite level before becoming eligible for free agency.

“I feel great,” Castillo said in a statement. “Every baseball player wants to have a dream like this become a reality. I’m happy I was able to accomplish this with the Mariners, and I want to thank everybody in the organization for treating me so well.”

Saturday’s announcement continues what’s been a massive year of spending for Dipoto’s front office, not coincidentally as the club eyes its first postseason berth since 2001. In December, Seattle signed reigning AL Cy Young Award winner Robbie Ray to a five-year, $115 million contract, the Mariners’ richest at the time under Dipoto and one quite similar to Castillo’s. In April, the club signed shortstop J.P Crawford to a five-year extension. Then in August, they locked up Julio Rodríguez to a megadeal that guarantees the star rookie $210 million and could become the richest in MLB history.

Castillo, who was acquired by the Mariners on July 30 in a blockbuster deal with Cincinnati ahead of the Trade Deadline, was not eligible to reach free agency until after the 2023 season. He’s been everything they’d hoped for, with a 2.83 ERA and 64 strikeouts, a franchise record for a pitcher in their first nine career starts with the Mariners. If they reach the postseason, he’ll likely be their Game 1 starter for the AL Wild Card Series, regardless of who they’d play.

"I'm very happy with the rotation," Castillo said. "We're all healthy. Hopefully, we can continue to work and see how far we can go for the next few years."

Moreover, Castillo has blossomed into one of the better righties since debuting with the Reds in 2017. Among pitchers age-29 or younger in that span, he ranks fourth in MLB with 924 strikeouts, fourth in innings (846 1/3) and seventh in strikeouts per nine innings (9.8).

“Luis has been one of the top pitchers in MLB over the past six seasons,” Dipoto said in a statement. “He is a dynamic power pitcher in the prime of his career with a track record of consistency. Bringing him to Seattle represented a key moment in our ongoing efforts to build a championship roster. Similarly, this deal illustrates our continued commitment to both the present and future of this team.”

The Mariners parted with three of their top five prospects to acquire Castillo, including infielder Noelvi Marte, MLB Pipeline’s No. 17 overall, emptying a chunk of their top-shelf talent that they spent three years accumulating and growing it into the No. 2-ranked farm system.

But Castillo, in the front office’s eyes, was worth it -- even if it would only retain him for a postseason push in 2022 and one year after. Now, the Mariners ensure that the arm they’ve been chasing for years will be the ace atop a rotation that is solidified for years.

Beyond Castillo, Ray is locked up through 2026 if he doesn’t exercise an opt-out after ‘24. Second-year standout Logan Gilbert isn’t eligible for free agency until after ‘27 and rookie George Kirby, who’s been arguably the AL’s most consistent starter in the second half, can’t reach the market until after ‘28. There is also a stable of elite arms in the pipeline on its way, headlined by Emerson Hancock, the club’s No. 2 prospect.

“Pitching drives the train,” in the words of Servais, and the Mariners have a lot of it at a premium. And after Saturday, they ensured that one of their best in the category will be here for what they hope leads a sustained winning culture.