Diekman's Flirt With Perfection a Major Reason for Athletics' Success

Veteran left-handed reliever Jake Diekman hasn't allowed a run all season in 17 appearances coming out of the Oakland Athletics bullpen. He's one of the prime reasons the A's are poised to lock up the American League West title.

He won’t get any MVP votes. Even on his own team, he’s not the most valuable reliever.

Without Jake Diekman, however, there’s no telling where the A’s would be. Where Oakland is – first in the American League West, 6½ games up on second-place Houston and a magic number of four to win the West – is pretty decent, and much of that has to do with Diekman.

The scoreless inning he threw Wednesday — the last two outs of the seventh inning and the first out of the eighth inning — provided the bridge between starter Mike Fiers’ sixth win (tied for fifth in the Majors) and closer Liam Hendriks’ MLB-leading 13th save.

It was Diekman’s 17th game, and in all of that time (17 innings), he hasn’t allowed a run. That’s the most scoreless innings for a pitcher this season, one more than San Diego’s Drew Pomeranz, himself a former A’s pitcher.

He’s closing in on the all-time single-season record for scoreless innings. The only pitchers in Major League history to have more innings in a season without allowing a run are Tyler Olson (20.0 innings for the Indians in 2017) and Karl Spooner (18.0 innings for the Brooklyn Dodgers in 1954).

He’s a lefty, and left-handers are supposed to beat up on lefty hitters. He has, holding them to a .174 batting average. But his true success has come against right-handers, who have just three hits in 34 at-bats against him, an other-worldly .088 batting average.

Diekman’s secret?

“I really don’t care if they hit the ball,” he said.

In part that’s because he’s got a good infield defense behind him, although the loss of third baseman Matt Chapman for the rest of the season has impacted that some.

In greater part, however, it’s because Diekman says if he can make the pitch he wants, he likes his chance. This is a reliever who has allowed just one inherited runner to score. That came when he buried a slider in the dirt and the Diamondbacks’ David Peralta golf stroked it for a walkoff single.

It was the exact pitch he wanted to make – nowhere near the middle of the plate. Peralta just did what hitters do, adjusting and hacking. Diekman can live with that.

“I just try to make my slider as best as I can,” Diekman said, saying his approach doesn’t vary that much whether he’s facing a right-hander or a lefty. “I try to miss with my heater in a right spot. I don’t want to miss out over the plate. I’m just trying to stay away from middle-middle.”

That slider is a pitch he’s modeled after the one thrown by Tampa Bay right-hander Chaz Roe, and while the left-handed Diekman had to look into a mirror to get the left-right thing ironed out, the slider has become a first-class weapon.

With Diekman’s 0.00 earned run average, the 1.23 ERA owned by Hendriks, the 1.29 of J.B. Wendelken and the 1.86 of Yusmeiro Petit, the A’s have quietly put together the most effective bullpen in baseball.

The A’s lead the major leagues with a bullpen ERA of 2.14. That’s not only more than half a run lower than the runner-up Dodgers, but it’s the best ERA by a team’s bullpen since the 1942 Cardinals’ 1.75, tied with the 2.14 ERA of the 1967 White Sox. The A’s club record is 2.35, set in 1990.

And Diekman likes where the group as a whole is heading – the A’s have a day off Thursday, then have 10 games to finish out the regular season and head to the playoffs, the first round of which is likely to start in Oakland.

“I think everyone here has a really good sense of where they need to be to be able to perform,” Diekman said recently. “Yeah it’s fun to watch.”

Follow Athletics insider John Hickey on Twitter: @JHickey3

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