3 rentals the Mariners could Use to restock the bullpen

Rental #1: Kenley Jansen

Kenley and his 429 career saves are reportedly as good as gone by the deadline in Boston. The 4X All-Star throws his 92 MPH cutter 90% of the time, but the lack of variance doesn't stop him from getting results. He's got a 2.89 ERA in 2024, with an impressive 33.4% K rate. His 1% chase rate indicates that guys are really swinging and missing in the zone, which is a testament to his cutter. His playoff experience as a World Series Champion, in conjunction with his 400+ saves, would be a huge addition to this Seattle bullpen. Obviously, Jerry and the Seattle org have demonstrated the ability to develop pitching, but it's difficult to artificially replace the value of a respected veteran with a resume like Jansen in the pen.

If Jerry were to call Craig Breslow about Jansen, it likely would cost close to nothing if the Mariners were willing to eat the remainder of Kenley's $16M salary. While the idea of not having to trade any prospect in the top 30 is an attractive prospect, most of us probably wouldn't name the Mariners as a typical suspect for eating salary in a trade as opposed to dealing from talent. John Stanton has expressed a willingness to spend money, so we can't rule it out.

Option #2: Paul Sewald

Imagine if the Mariners got their old closer back? Sewald hasn't been healthy for a good portion of the year but has a 2.57 in 31 regular season games for the Snakes. Paul is a prime example of the Seattle pitching lab, with a 5.50 career MLB ERA with the Mets in 125 appearances before closing 52 games for the Mariners over a three-year period. Sewald has a two-pitch mix, a 91 MPH four-seam, and a sweeper. He's a non-traditional closer without a big fastball similar to the Yankees closer, Clay Holmes. It may not be en vogue, but a closer needs to get outs. Who cares if the four-seam is 91 or 98, right?

If the Diamondbacks continue to fall down the Wild Card ladder, there's really no way Sewald stays in Arizona. Too many contenders will bid for his services, as guy with 9th inning experience who doesn't have a huge salary figure. Last year, he had a 30%+ K rate on both pitches, but that sweeper is what really makes Sewald special as a reliever. This is Paul's year to test the market, so he has a chance for a nice payday if he can show flashes of dominance down the stretch. What better place for the occasion than the park where he made himself a brand name reliever?

Option #3: Dylan Floro

The Nationals' pen has been sneaky competent this season, and Dylan Floro has been a huge part of that. He's carrying a 1.19 ERA this season in 30 games, he's been nails for over two months. He struggled last year, with a 4.76 split between the Twins and the Fish. He's only got 32 career saves, but he won't command the same price as a closer like Sewald. Floro will probably cost close to nothing, and relievers are difficult to gauge. My feeling about it is that most bullpen arms have great years and bad years. This looks like a career year for Floro, and I expect that to continue to a certain extent.

Floro is a sinkerballer, throwing it 46% of the time. He also throws a slider, four-seamer, and changeup, but his slider and sinker are his two best pitches. His 48.9% GB Rate is 77th percentile this season, while his 1.1% barrel rate is 99th percentile. That kind of consistent soft contact and groundballs mean more double plays and pop-outs.

Floro is in the bottom 2% in chase, and he doesn't generate a ton of swing and miss. He's going to rely on his ability to generate soft contact for outs, but that complements the skillsets of Santos and Munoz quite well. I love this proposal because of how realistic it is, the Mariners could get Floro for a project or org depth guy. Not much to give up, but it would be a huge lift for this bullpen!