So this befell the Cardinals on Friday night in Seattle ...

The Cardinals started the frame up 3-1 on the Mariners, but closer Trevor Rosenthal's ninth went double, walk, walk-off homer. For the Cardinals and their rooters, this is a somewhat familiar refrain.

As such, St. Louis manager Mike Matheny met with Rosenthal on Saturday and let him know he'll be taking a break from closing, the St. Louis Post-Dispatch reports.

Rosenthal's 2016 ERA now stands at 5.63. In 24 innings he's walked 21 batters, all unintentionally, and opposing hitters have an OBP of .429. More to the point, he's a closer who this season has on average allowed more than two base-runners per inning. As you would expect, Rosenthal has also worked the team's most important spots, as measured by Leverage Index. So he's not only hemorrhaged runs, he's also done so at inopportune moments.

To be sure, 24 innings isn't much, and given Rosenthal's highly successful pre-2016 track record, you'd normally be inclined to see if he can adjust, regress, and "sample size" his way out of this.

However, the Cardinals' late-inning struggles are a big reason why they're underplaying their run differential by five full games. There's already a lot of space between them and the first-place Cubs, and the NL wild card fray profiles as a crowded and compressed one. All of that is to say, the Cardinals may feel they do not have the time or the margin to allow Rosenthal to pitch his way out of this in important spots.

Trevor Rosenthal hasn't looked like himself this year. USATSI

As for what's going on with Rosenthal, it looks to be an issue of control and fastball command. This season, he's walked 17.7 percent of opposing hitters, and that's versus a pre-2016 career mark of 9.5 percent. Obviously, that 2016 figure embodies a huge loss of control and is a patently unacceptable number for a closer.

As for Rosenthal's vaunted fastball, it's still elite in terms of velocity, but he's spotting it in some less-than-optimal locations. Brooks Baseball tracks the percentage of pitches that a hurler "grooves," or leaves in the hitting zone, and as you're about to see Rosenthal is grooving his fastball well above established norms ...

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Thanks to his lack of control, hitters are swinging at his fastball roughly 10 percent less often than they were in 2015. When they do swing, though, they're doing damage: opposing hitters have an average of .338 and a slugging percentage of .471 against Rosenthal's fastball, which is a pitch he's going to almost 80 percent of the time this season. No longer in awe of his fastball, they're not biting on his changeup (swing rate also down roughly 10 percent), and they're swinging less on everything out of the zone, which are the pitches that often get whiffs or weak contact.

The elevated BABIP and his home run/fly ball percentage may portend improvement, but, again, the Cardinals don't have the room to see if that's the case or if this is something that won't correct itself given nothing more than time.

It so happens that the Cardinals have two ready replacements. Kevin Siegrist has been quite good when healthy and has manageable platoon tendencies as lefty relievers go. The more intriguing option is, of course, 33-year-old rookie Seung Hwan Oh, who's been exceptional in his first stateside season and had a long record of success as a closer in Korea and then Japan.

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Could Seung Hwan Oh be the answer in the ninth inning? USATSI

Oh has been outstanding this season (1.66 ERA and a 6.38 K/BB ratio in 37 games), and he's got the stuff to thrive in the role. Oh's fastball has a bit better than average velo, and his hard slider has strong 12-6 movement, which makes it a weapon against the opposite side. He's also got a workable changeup. Oh, and his sky-scraping nickname -- The Final Boss (!) -- most assuredly befits a late-inning relief ace.

For Matheny's part, the Post-Dispatch reports that the Cardinals plan on rolling with three options in the ninth inning: Siegrist, Oh and experienced closer Jonathan Broxton. However, there's the opportunity for someone to emerge, and it wouldn't be surprising for that someone to be The Final Boss.

The Cardinals had a closer who's struggling with no obvious near-term path to improvement, but they also have internal options to replace him, at least temporarily. It's getting late out there, and the blown leads keep mounting.

Matheny has never been a particularly dynamic thinker when it comes to running a bullpen, but he badly needed to show some adaptability when it comes to the team's closer struggles. He has. The 2016 season may hinge on it.