Dodgers’ Josh Fields won’t talk numbers, but his performance on the mound has been stellar

The ground rules for a conversation with Josh Fields are set right away.

“No numbers,” the Dodgers reliever said Sunday. “We don’t talk numbers.”

Fields knows there is a huge discrepancy between the 9.72 earned-run average he had in nine spring-training games and the sparkling 0.84 ERA he has posted in 21 regular-season appearances, a performance that has pushed the hard-throwing right-hander into a high-leverage role in one of baseball’s best bullpens.

But why jinx himself by looking at the stat sheet?

“I don’t know if I’d say I’m superstitious, but I am a little stitious,” Fields said with a laugh. “There’s a little bit of superstition, but the biggest thing is I don’t want anything, either good or bad, to get into my head.

“If it doesn’t look good, I don’t want to be defeated by looking at it and thinking, ‘This mountain is pretty tall to climb.’ If it does look good, I don’t want to get complacent and comfortable and not put forth the same effort.”

Fields, 31, has found a groove, using his 95-mph fastball and sharp knuckle curve to strike out 26 batters while walking four in 21 1/3 innings.

He came up huge again on Sunday, replacing starter Clayton Kershaw with runners on second and third and one out in the fifth and striking out Javier Baez with an elevated 96-mph fastball and Kris Bryant with a high-and-away 97-mph fastball to preserve a 6-4 lead.

Fields retired the side in order in the sixth to earn the win, and Sergio Romo, Adam Liberatore and Kenley Jansen covered the final innings for a bullpen that leads the National League with a 2.76 ERA.

“It’s nice to pick up Clayton,” Fields said, “because he’s picked us up way more times than we’ve been able to do for him.”

Fields, on the advice of pitching coach Rick Honeycutt and bullpen coach Josh Bard, made a mechanical adjustment in his lower half in late-March that he said added movement to his fastball and gave him “a boost of confidence.”

Though he was optioned to triple A and recalled twice in April, Fields, acquired from Houston last Aug. 1, has solidified his spot as one of the team’s primary setup men along with Pedro Baez.

“You can see his confidence on the mound, the conviction with the fastball, being able to strike with the breaking ball,” manager Dave Roberts said. “Right now, he’s found a nice lane to throw in, and he’s been really consistent.”

Pain management

Brandon McCarthy expects to make his next start — and avoid a 15th trip to the disabled list— after an MRI test confirmed that the right-hander has patellar tendinitis in his right knee.

McCarthy was pulled from Saturday’s 5-0 win over the Cubs after throwing 79 pitches over six scoreless, two-hit innings to improve to 5-1 with a 3.28 ERA. The knee has bothered McCarthy periodically throughout the season.

“There have been really good days and some bad days,” McCarthy said. “[Saturday] was the first day where it got pretty sore. I didn’t feel it at all the start before. It’s been there all year, so we’ve learned how to manage it.”

Short hops

Outfielder Franklin Gutierrez left Sunday’s game in the first inning because of a stomach-related illness and was replaced by Yasiel Puig, who singled and scored in the third, hit a two-run homer in the seventh and made a long sprint into the right-field corner to catch Anthony Rizzo’s foul ball before slamming into the wall. … Roberts doesn’t expect center fielder Joc Pederson, on the seven-day concussion DL after his collision with Puig on Tuesday night, to be activated during a seven-game trip to St. Louis and Milwaukee. “He’s getting a little better every day,” Roberts said, “but there’s still some sort of haze going on.” … Former Dodgers manager Tommy Lasorda, 89, was released from the hospital Sunday after a procedure to replace his pacemaker. He is at home and resting comfortably, according to the team.

mike.digiovanna@latimes.com

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