SAN DIEGO -- The Pirates’ resilience appears set for yet another test, and not because they dropped a 4-3 decision against the Padres on Thursday night.

A team that already has 10 players on the injured list saw its top innings-eater exit prematurely at Petco Park. Right-hander Trevor Williams, a native San Diegan who had a loud cheering section on his side, left in the fourth inning after 73 pitches with what the Pirates termed “right side discomfort.”

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“To be here, home, in front of his family and friends, you know he had to be hurting to come out of the game,” Pirates shortstop Kevin Newman said. “That’s hard to watch, and I feel for him.”

Williams left Petco Park without speaking to reporters, and the Pirates provided no additional medical updates. If the issue is enough to put Williams on the injured list, he would be the club’s 20th player to hit the IL in 2019. Yet they remain above .500, at 21-20.

“Next man up,” said veteran left-hander Francisco Liriano, who was literally the next man up and threw 1 1/3 innings of hitless ball after being pressed into emergency duty. “We don’t know how bad it is for Trevor. But if somebody gets a chance to pitch, hopefully, they do the job.”

Said Newman: “It’s part of the game. Injuries, you hate to see them, but it’s kind of been the storyline of our team this year. Next person up filling in a spot is not just a body standing in there. They’re somebody we’re looking to make an impact. That’s something our team knows and something we’re looking to do.”

Righty Richard Rodriguez did not fare as well in relief as Liriano did. In the sixth, Rodriguez surrendered Ian Kinsler’s game-changing, three-run home run. That blast turned a 2-1 Pirates lead into a 4-2 deficit. Rodriguez has allowed eight home runs in 19 2/3 innings.

Gregory Polanco got Pittsburgh within a run with a 423-foot, line-drive homer to right in the eighth, but the Pirates were unable to make a dent against Padres closer Kirby Yates in the ninth.

Pirates first baseman Josh Bell went 0-for-4 and saw his 15-game hitting streak come to an end. With that, the longest active streak in the Majors now belongs to the Cubs’ Javier Baez with 14 games.

In the fateful fourth, Williams struck out Wil Myers with a 92 mph fastball for the second out of the inning, then put his hand on the right side of his torso and grimaced. He gestured toward the Pirates’ dugout and left the game at Petco Park without throwing any warmup pitches to test the injury.

The Pirates trailed 1-0 when Williams left the game. Padres right fielder Franmil Reyes hit a 404-foot home run on a 3-2 fastball in the top of the third inning. Williams escaped a bases-loaded, one-out jam in the first inning when he struck out Alex Dickerson and got Myers to ground out to shortstop.

“He was competing like he always does,” manager Clint Hurdle said. “He was making pitches. … He was doing his thing. Sleeves were rolled up; he was going to work.”

Williams, 27, leads the Pirates with 54 innings pitched and had lasted at least six innings in each of his previous eight starts this season. He had five strikeouts in 3 2/3 innings Thursday and allowed two hits and one walk while lowering his ERA to 3.33.

Williams graduated from Rancho Bernardo High School in San Diego and was pitching at Petco Park for the second time in his four Major League seasons.

Memorable night for Newman

Like Williams, Newman was playing in front of friends and family at Petco Park. But he was doing it for the first time. Newman was born in suburban Poway and attended Poway High School.

He went 2-for-4, scored a run and blooped a double to right for his first extra-base hit since May 9 at St. Louis.

“It was surreal,” Newman said, “everything about it -- getting to go out there and play in front of my family in my hometown, and my friends, it was something special. To be able to step onto that field and make another dream come true, it’s just an awesome feeling.”

Newman might have had a three-hit night if not for his counterpart at shortstop. Manny Machado robbed Newman in the third inning with a diving stop and a throw to first from his knees.

“You see all the highlights of Machado on ESPN, all the amazing plays he makes,” Newman said. “There’s another one to add to his resume. Unfortunately, it was against me. But it was a great play. I came back, got a couple hits. Can’t complain.”