Two in-house relief options for the Mariners bullpen

While it’s far from the only problem with the team, the “B” side of the Mariners bullpen has been an issue this season, as the team has cycled through various names trying to find some surehanded help to prop up an injury-ravaged ‘pen. With the latest injury update forecasting that Carlos Vargas, Matt Brash, and Cooper Criswell won’t be back until mid-to-late August (Vargas and Brash) to late August or September (Criswell), picking up bullpen help at the deadline is obviously on the Mariners’ shopping

list, but with the market shaping up to be an extreme seller’s market, the Mariners would find themselves paying top-shelf prices to acquire bullpen pieces while the offense continues to flounder.

Instead of looking for outside help, the Mariners might be better served by keeping their prospects and looking internally. Obviously, the first two names to jump to mind – especially after their sterling outings at the Futures Game last weekend – are Kade Anderson and Ryan Sloan, the two-headed pitching monster currently destroying the Texas League. However, Jerry Dipoto said in conversation on Friday that the team is going to be very mindful of Anderson’s innings, in particular: there’s a number of innings they want him to get to, and the math has to work out considering what his role would be at the big-league level. The situation is similar with Sloan, who is even younger than Anderson although with more pro ball experience; the Mariners are laser-focused on ensuring that they won’t be robbing Peter to pay Paul, so to speak, and artificially accelerating the timeline or development of either of the two pitchers in order to paper over cracks at the big-league level.

But there are are pair of relievers, recently promoted to Tacoma, who have been pitching well enough to deserve a shot, both mentioned in conversation by Dipoto. The first is a familiar name for those of you who were heavily plugged in during Spring Training: righty Charlie Beilenson, a fifth-round senior sign in 2024 out of Duke – one of the senior signs the Mariners used to save money for Ryan Sloan, funnily enough, but Beilenson is a legitimate prospect. The club had designs on fast-tracking him in 2025, but an injury suffered in spring training kept him out for most of the year. Beilenson got back on track this spring, pitching both with the big-league club in spring training and for Team Israel in the WBC, experience that Dipoto said was invaluable for the young reliever, given an opportunity to share the field with some of the game’s best and feel like he belonged. At Arkansas this season, Beilenson is striking out over a third of batters faced and holding hitters to a .187 average, despite not having the loudest stuff – his fastball hangs out in the lower 90s, mid-90s when it’s going well, and he couples that with a slider-changeup combo that accounts for most of his whiffs. The big selling point with Beilenson is his plus command, although he walks a few more guys than you’d expect out of that profile. He has eight saves for Arkansas, leading all pitchers in the system – familiar territory for Beilenson, who was a Stopper of the Year finalist at Duke and tied the school record for saves in a single season.

Here’s one of my favorite Charlie outings, from July 7 against the Amarillo Sod Poodles: technically this is low-leverage because it was an extra-inning game tied at 2 before the Travs scored eight runs in the top of the 10th, but Beilenson still struck out the side to put an exclamation point on a thrilling Travs win. Vimeo wasn’t cooperating with me so please excuse the Bluesky embed (and click through to see all three strikeouts, two swinging and one called to end the game).

The other arm Dipoto mentioned was Reid VanScoter, also recently promoted to Triple-A. A longtime resident in Seattle’s system, VanScoter could be an option for the Mariners should they want to add another lefty to the pen. In his second tour of the Texas League, VanScoter is striking out a career-high 31% of hitters thanks to what Dipoto described as a mechanical change; however, that spike in strikeouts has come at the cost of some of his command, as he’s also walking a career-high number of hitters. He’ll need to calm that down in order to earn a look at the big leagues and unseat Josh Simpson as the other lefty option in the ‘pen.

One name that didn’t come up but is definitely on most prospect-heads’ radar is Teddy McGraw, a promising pitcher whose journey to the bigs has been delayed by multiple arm injuries but who possesses one of the best curveballs in the system. The Mariners have been ramping up McGraw’s usage at Double-A late in June, going from having him pitch every four days to every other day. McGraw’s arc is a little longer than the other two, as he continues to gain experience in the upper minors and just adjust physically to the rigors of professional baseball, even while healthy, but he’s a name to monitor.

Another longer-path name to know is Brock Moore, who was promoted to Double-A in early June after mowing down hitters at High-A. The 6’6” former Oregon Duck is still searching for his command in Arkansas, but he’s the “stuffiest” guy listed here, with a fastball that can kiss triple digits and a two-plane slider that combine for massive whiff rates but also massive walk rates.