MILWAUKEE -- For a pitch to get a nickname, it has to be pretty special.
The origins of Will Smith's slider being called "the slider of death" are unknown, but the moniker certainly fits the effectiveness of the pitch.
Although other relievers throw sliders at a higher percentage -- Smith entered Thursday using the pitch 30.7 percent of the time -- it's hard to argue any pitcher has used any type of pitch better this season.
Hitters are just 4-for-45 (.089 batting average) against Smith's slider this season, as left-handed batters have looked particularly foolish trying to attack the pitch.
"Really? Nice," Smith said when told of the lack of success opposing hitters have had against his slider. "I've got to get those other four guys out. So it still needs to get better."
Smith didn't begin throwing a slider until he was in Double-A in 2011. He was approached by the coaching staff about adding the pitch to his repertoire in an effort to help the then starting pitcher get through a lineup easier.
"They were like, 'Have you ever tried throwing a slider?' Smith said. "I was like, 'I did in high school. Guess I wasn't doing it right because it kind of hurt my arm and I backed away from it.' He goes, 'OK, we want you to maybe start throwing it.' "
Smith then proceeded to walk around the clubhouse of the Northwest Arkansas Naturals and asked fellow pitchers to show him their slider grip. He settled on Kevin Chapman, a left-handed pitcher who has appeared in six games this season for the Houston Astros.
"He said, 'When you start throwing it, try to make it move this much . .. next time this much, then this much until you get comfortable enough that it turns into a slider.'" Smith said. "That's just kind of where it took off. Just grip it and throw it."
Prior to Smith retiring Ruben Tejada and Daniel Murphy on sliders in a scoreless eighth inning Wednesday night, the left-hander had the same exact success with the pitch as he did in 2013 with the Royals.
Smith held opponents to a 4-for-43 clip on his slider in 2013, proving the pitch isn't a fluke.
"You can't pick up the spin," Brewers manager Ron Roenicke. "The good sliders, you can't see the spin. The spin is too fast. You think it's a fastball, and you start your swing and it's gone. He's got a very good curveball, too, that he uses against right-handers. But his slider has been almost unhittable for lefties."
Smith made his major-league debut with the Royals in 2012, tossing 89 2/3 innings in 16 starts. He spent a good portion of 2013 in Triple-A but feels last season is when the slider really became a go-to pitch for him.
He threw 133 sliders in the big leagues in 2013, allowed just four hits and recorded 27 strikeouts.
"Last year for sure, because I was still starting and using it," Smith said. "Getting lefties out, getting righties out. Then when I went to the bullpen that's when it got harder and sharper and tuned up a little bit."
Of the 438 sliders Smith has thrown in 68 big-league appearances, hitters have just six extra-base hits -- two doubles and four home runs. The last home run hit against Smith's slider came on Aug. 17, 2013 when Prince Fielder connected on a 2-1 pitch.
Other than Fielder, Curtis Granderson (May 23, 2012), Pedro Ciriaco (Aug. 26, 2012) and Jesus Montero (July 19, 2012) are the only other players to have homered against Smith's slider.
"It's one of the nastiest lefty sliders I've ever seen," Brewers catcher Jonathan Lucroy said. "They are calling it the 'slider of death', I know that. He's struck out both righties and lefties with it. He's got good stuff."
While it is a weapon Lucroy always has in his back pocket when catching Smith, he doesn't want to go to the slider too much when the left-hander has a curveball and changeup he can go to off his mid-90s fastball.
"I don't want to over throw it at all," Lucroy said. "You can't just throw it every pitch. You have to compliment it with his heater and other pitches. You have to be able to mix to keep guys off it. If guys go up there and start sitting on it and you get it while they are sitting on it, they are more likely to put a better swing on it."
Having four pitches at his disposal has helped Smith to be one of the best relievers in baseball this season. Smith has a 0.91 ERA in 33 appearances, making Milwaukee's deal to acquire him for aging outfielder Norichika Aoki look like an overwhelming success.
"I can use (the slider), but I still have the other two pitches in my back pocket if I need them, which is a comforting feeling to me," Smith said. "Some nights, say my slider's not there and they're not swinging at it -- it's not like full panic mode. I have two other pitches I can fall back on. Which is nice."
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