Over the course of his career, Kenley Jansen has been one of baseball's most effective relievers, a role where effectiveness is at a premium and consistency even more so.

In 12 MLB seasons, Jansen holds a 2.38 career ERA, has never posted an ERA above four and has posted an ERA below three in all but three seasons. He entered Thursday with an ERA of 2.15 this season.

And yet, on the occasions where it does fall apart for Jansen, no reliever delivers a slow-motion trainwreck quite like him.

The Dodgers got a double dose of that in the final two games of a key four-game series against the San Francisco Giants this week, The first blown save was more of a quick-hitting, generic awfulness: a Buster Poser single then a Wilmer Flores homer within five pitches to blow a one-run lead the Dodgers would never get back.

The second blown save on Thursday, though, that one deserves a more complete breakdown.

Anatomy of a Kenley Jansen blown save

Jansen entered the game with a 3-1 lead, and that action alone could be considered the beginning of the trainwreck considering Jansen had thrown 27 pitches the previous night and blown his last two saves (Coors Field also got to Jansen on Sunday).

Dodgers manager Dave Roberts still put Jansen in. For a few minutes, it looked like the right move. Jansen struck out Mike Yastrzemski on three pitches, allowed a single (but not a homer) to Flores, then struck out Alex Dickerson.

The troubles really began when Donovan Solano hit a double to center field. Jansen recovered enough to get ahead 1-2 on the next batter, pinch-hitter Jason Vosler, but then the rookie worked a full-count walk to load the bases. Jansen hadn't yielded a run at that point, but he had allowed three baserunners and thrown 22 pitches, adding up to 49 pitches in the last two days.

What happened next really wasn't Jansen's fault, though. Thairo Estrada hit a routine grounder to shortstop Chris Taylor, who decided to throw to second base, where second baseman Sheldon Neuse awaited to do ... this:

That play was initially called an out for the Giants, but replay overturned the call on the field and cut the deficit to 3-2 with the bases still loaded and two outs.

"I just think right there in that situation if we stretch, we get the guy and there's no replay. But that's part of baseball," Roberts said after the game.

Darin Ruf followed that up by racking up another full count, then swing his bat well past home plate on a ball out of the zone for strike three. Except, that's not how first base umpire Ed Hickox saw it.

It should be noted that Jansen benefited from some generous strike calls earlier in that plate appearance — a 2-0 pitch was clearly outside and should have been ball three — but Roberts was still understandably upset. The manager immediately threw his hat onto the field and received an ejection.

"There's no doubt in my mind that he went and the game should've been over," Robert said after the game.

Roberts' ejection left bench coach Bob Geren to take Jansen out after walking in a run to blow the save. Once again, that's not what happened. Despite having thrown 30 pitches up to that point, Jansen stayed in the game to face LaMonte Wade Jr.

You probably know where this is going:

Jansen was finally pulled after that two-run single, with Dodger Stadium booing him for a second straight night.

None of this happened quickly, it should be said. MLB.com reporter Juan Toribio tweeted Jansen's entry to the game at 9:36 p.m. and his exit at 10:02 p.m. Jansen's collapse occurred over 28 excruciating minutes, a little under 1.2 pitches per minute.

A one-pitch Phil Bickford appearance and scoreless bottom of the ninth would end the game, a 5-3 loss for the Dodgers that pushed them three games behind the Giants in the NL West standings. Had Jansen gone 2-for-2 in save opportunities for the series, they would be in first place right now.

To summarize, Jansen could have earned the save if he had just recorded one more strike against Vosler. He could have earned the save had Neuse extended his arm out a couple feet. He could have earned the save if a clear swing was called a strike. He could have had a stressless night had Roberts not gone with a clearly struggling reliever who had thrown 27 pitches the previous game.

And yet, none of that happened, and Jansen was left to blow his third straight save, the first such streak of his career. Baseball can be a cruel sport.

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