SAN DIEGO -- The Padres entered the final eight weeks of the season on Friday night. It’s not a sprint to the finish just yet, but it’s no longer the proverbial marathon.

With every misstep, there’s less road ahead to correct course.

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The Padres had such a misstep to open a three-game series against the last-place D-backs, dropping an 8-5 decision at Petco Park. The Padres squandered an early five-run lead and allowed eight singles in one inning along the way.

“No doubt, it’s disappointing,” Padres manager Jayce Tingler said.

With the defeat, the Padres find themselves closer to the team pursuing them than they are to the team they are pursuing. The Reds sit 2 1/2 games behind the Padres for the second National League Wild Card spot. The Padres, meanwhile, are 3 1/2 games back of the Dodgers for the top NL Wild Card position.

“We have to play good baseball in order to win,” Tingler said. “It’s now. We’ve been spinning our wheels at times -- playing good, playing bad, back and forth. We’ve got to get it going, no doubt about it.

“It definitely hurts. … You get the five-run lead, and everything turned quickly.”

Padres starter Ryan Weathers was handed a 5-0 lead after two innings, thanks greatly to Trent Grisham’s two-run home run into the right-field porch and Jake Cronenworth’s two-run double. But the rookie Weathers gave two runs back in the third inning and couldn’t record an out in the fourth.

In that fourth inning, the D-backs stormed to the lead with six runs. Weathers and reliever Craig Stammen allowed a combined eight singles and one walk in the frame.

Weathers yielded four straight hits to open the inning before Tingler called to the bullpen.

“I felt good throughout the whole outing,” Weathers said. “Regardless of what the results say, I felt a lot of positives. I pounded the strike zone like I wanted to. They just got some good hits. That’s baseball. That’s how it shakes out sometimes.”

The D-backs’ six runs matched the biggest inning against the Padres this year. And they had the honor the first time with a six-run fifth inning on Opening Day. The Padres rallied to take the opener, but the bats weren’t up to the task this time around.

Arizona lefty Caleb Smith was chased during the Padres’ five-run second inning, leaving San Diego with a lefty-heavy lineup (Adam Frazier, Cronenworth, Eric Hosmer and Grisham) to take their cuts against righty reliever Matt Peacock. Instead, Peacock held them at bay with 4 2/3 scoreless innings. He dispatched the Padres on seven pitches in the fourth inning and eight in the fifth.

“We know he’s got a good power sinker,” Tingler said. “He was pounding the zone with a lot of strikes. Unfortunately, we were putting the ball on the ground with that sinker. We weren’t able to elevate and get going.”

“Get going” is what the Padres are trying to do in the macro sense. They are 9-9 since the All-Star break, but they have nine games left against the Dodgers and seven against the first-place Giants. If they do “get going,” they can take huge strides in the stretch run.

“I feel like, really, we’ve been on just two good rolls throughout the year,” Tingler said. “In one way, it’s frustrating. But another way, one that gives us hope and a lot of faith, is we know another [roll] is coming.

“We wanted it to happen tonight -- you want to get on a roll and get going. But I do think it’s going to happen.”