When Mariners president of baseball operations Jerry Dipoto has joined Seattle Sports for his last few weekly interviews, he has made it clear that he’s in the market for another starting pitcher. And that’s not a slight at the five guys Seattle currently has.

More M’s trade deadline targets: Relievers to boost ‘pen

The foursome of Robbie Ray, Logan Gilbert, Marco Gonzales and Chris Flexen has been solid all year long and is a major reason the Mariners surged over the last month. Every member of that group has also made each scheduled start they’ve had this year as they’ve been remarkably healthy.

The fifth man in the rotation is rookie George Kirby, and the key word there is rookie. The Mariners are doing what they can to conserve Kirby’s workload as he has a limited track record of throwing innings at the pro level.

Currently, the Mariners’ depth behind their current five starters is not great. If one of those five were to go down, that would mean either Matt Brash or Tommy Milone would move over from the bullpen, or Justus Sheffield or Darren McCaughan would be recalled from Triple-A Tacoma.

The Mariners clearly don’t want that to be the case in a stretch run, so expect them to be hitting the phones hard looking for another starter before the Aug. 2 MLB trade deadline. They may also be seeking one who could continue to help them next year. While Ray, Gilbert, Gonzales and Kirby are all under contract for next year and beyond, Flexen has accumulated enough innings to make his club option for 2023 turn into a player option. He could choose to bet on himself in free agency, leaving at least one of the five spots in the rotation open for 2023 unless Seattle acquires a controllable starter this deadline.

Here are a number of the better starting pitcher options the Mariners could go after before the trade deadline.

• Cincinnati’s Luis Castillo and Tyler Mahle

The Cincinnati Reds are a dumpster fire who are openly tanking after selling off many of their most valuable assets this offseason. Case in point, Jesse Winker and Eugenio Suárez are now members of the Mariners after an offseason deal.

The Reds still have two very capable starters in Castillo, a 29-year-old two-time All-Star, and Mahle, a 27-year-old right-hander who has been very solid the last few years. The organization held onto both this season, but they could also be on the move this deadline.

Both are signed through 2023 and Castillo figures to be the more valuable of the two as he has a 2.77 ERA in 13 starts this year, his second All-Star campaign. He may be the biggest name to be dealt this deadline season unless Juan Soto gets traded by Washington.

Mahle is the younger of the two, and after posting ERAs of 3.59 and 3.75 the last two seasons, he’s at 4.48 through 18 starts. Many of his advanced metrics look very good, however.

Both Castillo and Mahle make plenty of sense for the Mariners because they’re pitching well and are signed through the end of next season.

• Arizona’s Madison Bumgarner, Zach Davies, and Merrill Kelly

Like the Reds, the Diamondbacks find themselves in last place in their division. They also have some starting pitching that should interest the Mariners and other playoff contenders.

First things first, Bumgarner. No, the 32-year-old southpaw hasn’t been the same All-Star regular since signing with Arizona that we grew accustomed to while he was with San Francisco, but he’s a proven arm who has been a solid starter this season, posting a 3.71 ERA with 78 strikeouts in 104 1/3 innings across 20 games. He’s also arguably the best postseason pitcher of all time and is signed through 2024. A hurdle, though, is that Bumgarner is set to make $37 million over the next two seasons.

Davies, 29, has made just 15 starts this year, but he appears to be closer to his 2020 form than his 2021 form. Two seasons ago, he had a 2.73 ERA and 3.88 FIP. Last year, his ERA was 5.78 and his FIP was 5.45. In 2022, Davies has a 3.94 ERA and 4.25 FIP. His hits and walks per nine innings are around or below his career averages. Davies isn’t a sexy name by any means, but he is a solid back-end arm that could help in terms of managing Kirby’s workload or filling in if someone gets hurt. Davies is on the IL right now with a shoulder injury but is nearing a return. He’s a free agent after this season.

Kelly, 33, has posted a 3.29 ERA and 3.35 FIP in 110 1/3 innings (19 starts). Like Davies, Kelly is a low strikeout guy, but he’s allowed only seven homers this year and has a fairly low walk rate. Kelly is only in his fourth MLB season despite his age, but he, like Flexen, shined in Korea before finding success in the big leagues. He’s signed through 2024 and has a club option for 2025.

• Colorado’s German Márquez and Chad Kuhl

Márquez has been a great pitcher for the Rockies for most of his career and has been the subject of trade rumors for a few years now, but the right-hander has struggled in 2022 with a 5.47 ERA and 4.87 FIP while allowing a career high in home runs per nine and tying his career high in hits and walks per nine. He’s also averaging a career low in strikeouts per nine.

Márquez still has a proven track record while making half his starts at hitter friendly Coors Field, is just 27 years old and is signed through 2023 with a club option for 2024. He could be a player that fits the Mariners not just for the end of this season, but also for the next year or two if the 2021 All-Star can turn things around.

As for Kuhl, the 29 year old has put up his usual numbers in his first season with the Rockies, posting a 4.48 ERA and 4.59 FIP while pitching to contact. Kuhl started the year pitching very well, but his numbers have risen up thanks to a poor July in which he has a 9.00 ERA in four starts. He’s a free agent after this year.

• Oakland’s Frankie Montas and Paul Blackburn

The A’s made it clear they were aiming to go through some bad years this past offseason when they traded a number of key players such as stars Matt Olson and Matt Chapman as well as lefty starter Sean Manea.

Oakland’s fire sale is expected to continue at the deadline, and the team has a number of pitchers who will likely be wearing new uniforms come Aug. 3.

Two of those arms are starters in Frankie Montas, who finished sixth in Cy Young voting last year, and Paul Blackburn, Oakland’s lone All-Star this year.

Montas has been on the trading block since Oakland’s fire sale began this offseason. He’s pitched well despite the noise, posting a 3.16 ERA and 3.24 FIP in 18 starts with 105 strikeouts. After an injury scare against the Mariners at the beginning of this month, the talented right-hander returned over the weekend, throwing three scoreless innings against the Tigers.

Montas, 29, is signed through 2023, so he could help a contending team not just this season but next year as well.

Blackburn, 28, has made 19 starts this season and has a 4.35 ERA and 3.93 FIP over 101 1/3 innings. In addition to throwing against the Mariners regularly since 2017, Seattle knows Blackburn well as he was part of the organization in the second half of 2016 before being traded that following offseason. Blackburn is under club control through 2025, so he may cost more than you’d think when looking at his season numbers and career totals.

• Pittsburgh’s Jose Quintana

The Mariners traded for a veteran southpaw from the Pirates last deadline and it worked out well. What about doing that again?

Last year, the Mariners added Tyler Anderson to stabilize the rotation. He did that in a big way making 13 starts for Seattle down the stretch.

Quintana, 33, has a 3.70 ERA and 3.27 FIP for Pittsburgh this year in 19 starts after spending most of the previous two years as a reliever. That could make him a good target for the Mariners as he has the ability to both work out of the pen or make starts in the rotation. Both could be important due to Kirby’s workload questions as well as the potential for an injury to any one of Seattle’s current five starters.

Quintana is on the final year of his deal so he would likely be a rental for this season only, just like Anderson was.

• Kansas City’s Zack Greinke

Greinke, 38, returned to his first franchise in the Royals this past offseason and has been a decent starter, posting a 4.64 ERA with a 4.58 FIP. He’s barely missing any bats (4.9 strikeouts per nine) and allowing over 10 hits per nine innings, but his status as a big name with playoff experience will have him potentially on the move this deadline.

Does the 19-year veteran make a lot of sense for the Mariners? Not at this moment, no. But again, there’s still plenty of time between now and the deadline for something to go wrong and the team needing even more starting pitching. The Mariners also know Greinke very well (18 career starts against them), which could make him an intriguing option since they know what they’re getting.

Additionally, Dipoto has traded for Greinke before, acquiring him from Milwaukee in 2012 while he was Angels general manager.

• Detroit’s Michael Pineda

Hello, old friend!

Michael Pineda, a rookie All-Star for the Mariners way back in 2011, is now 33 years old and pitching for the disappointing Tigers.

Pineda hasn’t done too well this year with a 5.27 ERA and 5.84 FIP, but he’s expected to move as a buy-low option this deadline as Detroit is in last place in the AL Central and has a plethora of young arms at or nearing the big league level.

Though Pineda has not pitched well in 2022, he had a 3.62 ERA and 4.21 FIP last year and a 4.01 ERA and 4.02 FIP in 2019, so there has been some recent success.

I don’t think the Mariners would go this way given his poor 2022 performance and that he’s on an expiring contract, but if something comes up between now and the Aug. 2 deadline, he would be someone who shouldn’t cost the team much at all in terms of prospects.

• Los Angeles’ Noah Syndergaard

I think the slumping Angels will trade Syndergaard, but I don’t think they’ll make a trade with a division rival like Seattle unless the M’s make an extremely good offer. That wouldn’t make too much sense for Seattle given Syndergaard is making $21 million this year and has made just 14 starts this year.

The 29 year old has been solid when healthy, posting a 4.00 ERA, 4.07 FIP and allowing just over eight hits per nine innings, but he’s not missing many bats (seven strikeouts per nine).

Someone will swoop up Syndergaard – especially if the Angels eat some money to facilitate a deal – but I don’t see it being the Mariners.

• Surprises

I’m not going to list any additional names here, but during every trade deadline and offseason there seems to be at least a few players who get dealt that no one was really expecting. Heck, I don’t think anyone anticipated the Mariners landing Winker and Suárez prior to the season starting.

As such, the Mariners could pull off a surprise deal for a starting pitcher that isn’t on most people’s radars. Even with prospect graduations of Julio Rodríguez, George Kirby and Matt Brash, the team still has enough talent in the farm and other places (like the bullpen) to get something notable done.

Lefko: Mariners must add at trade deadline, but it shouldn’t be Soto

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