Why Mariners’ latest waiver claim has future closer potential

The Toronto Blue Jays and Seattle Mariners have swapped quite a few players over the past few years, including Yimi Garcia, Justin Turner and Jonatan Clase. The most recent player to go from one of these teams to another is right-handed reliever Hagen Danner, whom the Mariners just claimed off of waivers from Toronto.

Danner, 26, is a catcher-turned-pitcher who's overcome a lot of adversity to get to where he is now. Not only did he successfully make a transition between positions, but he also faced exactly one batter in his big-league debut in 2023 before an injury wiped out the rest of his season. Grinding so hard to make it to The Show just to exit your debut after recording one out is the ultimate gut punch.

Danner returned to action in 2024, but he didn't make it back to the big leagues. Instead, he made 34 appearances in the minors, posting a 3.06 ERA while recording seven saves along the way. He didn't post any numbers that'll blow you away, but a look under the hood shows that he could be earning some saves in Seattle in no time.

Hagen Danner has 'future closer' written all over him for the Mariners

Back in 2023 before his debut, MLB.com named Danner as the Blue Jays' potential future closer, citing his three-pitch repertoire that's highlighted by a sharp slider, blazing fastball and a "solid" curveball. The righty functioning as the club's Triple-A closer only amplified the buzz surrounding his likely future role.

Now that he's in the Mariners organization, it's likely this is where he'll land, maybe even during the 2025 campaign.

Danner absolutely pounds the zone with all three of his pitches and can call all three of them above-average offerings. His fastball sits in the mid-to-high 90s while his slider (or "slutter", as he likes to call it) sits at around 88 miles per hour. His high-70s/low-80s curveball gives him a third pitch that's around 10 miles per hour different than the other pitches in his arsenal.

Having at least two solid pitches is a must for any relief pitcher. Just look at the likes of Aroldis Chapman (FB/SL), Devin Williams (FB/CH), Josh Hader (FB/SL) and Ryan Helsley (FB/SL). Danner has the unique distinction of having an extra tool at his disposal.

This past season, Danner induced whiffs at a 26.5 percent clip in Triple-A, while his curveball was at a jaw-dropping 50 percent. Opposing batters clearly aren't having a good time while he's on the mound. His strikeout rate dropped a bit in 2024 compared to where he was in 2023, but he's not far removed from punching out just under 13 batters per nine innings in a season. He's got some filthy strikeout potential, and having that third pitch to fall back on is crucial.

Over the years, the Mariners' player development staff has received rave reviews for how they turn one man's trash into their treasure on a yearly basis. This past season, they turned the likes of Collin Snider, Trent Thornton and Tayler Saucedo into reliable relievers who should all play important roles in their 2025 bullpen.

Danner routinely sits in the strike zone, boasts three solid pitches, and has excelled at limiting baserunners throughout his minor league career. If he can maintain this arsenal and his ability to overpower the opposition on the mound in the coming season, don't be surprised to see him earning some ninth-inning chances at the big-league level.