SAN DIEGO -- There were plenty of question marks on the Padres’ roster entering the 2020 season. The bullpen was not supposed to be one of them. But bullpens are often fickle, and on Sunday, the Padres' top two back-end arms cost them their best start since 1984.

For a brief moment, the Padres were the only remaining unbeaten team in baseball. That was short-lived. Emilio Pagán allowed two runs in the eighth, and Kirby Yates surrendered two more in the ninth, leading to a 4-3 loss to the D-backs at Petco Park that dropped the Padres to 2-1.

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Not that one game should change any of the lofty projections for the San Diego bullpen. But Yates and Pagán clearly weren’t the best versions of themselves. Pagán allowed the first three hitters he faced to reach base, as the D-backs turned a 1-0 deficit into a 2-1 lead. After Greg Garcia’s game-tying single in the bottom of the frame, Padres manager Jayce Tingler called on Yates.

Typically one of the best in baseball at spotting his fastball, Yates’ command of the pitch was practically nonexistent on Sunday. He walked consecutive hitters to load the bases before Ketel Marte put Arizona on top with a sacrifice fly. David Peralta tacked on an RBI single.

“After today, we're going to move forward,” Tingler said. “I've got zero issues [with the bullpen] moving forward. When you're carrying a 1-0 lead, you expose yourself, especially with those hitters over there, as skilled as they are.”

The Padres took that 1-0 lead courtesy of a third-inning home run from Eric Hosmer, but they failed to build on it, despite a handful of opportunities. San Diego recorded nine walks and six hits but left 12 men on base.

“We had some chances, had guys on base and just didn't cash them in,” Tingler said. “We just couldn't get that hit to get us going. They stayed around, stayed around, and they're a really good team.”

Good enough to break through against two of the best relievers in baseball. Pagán posted a 2.31 ERA last season with 12.3 strikeouts per nine innings. Yates notched a 1.19 mark with 15 K/9 and was first-team all-MLB. Neither of the two looked the part on Sunday.

In a 60-game season, bullpen hiccups are bound to sting a bit more than they otherwise would. But the Padres aren’t fretting, given the track records of both Pagán and Yates. They’ve also built one of the deepest relief corps in baseball behind those two. Six other relievers combined for 7 1/3 innings of one-run ball this weekend.

The fact is: If Pagán and Yates are the two biggest issues through three games, it was probably a successful opening weekend in San Diego. (And if not for a sprawling ninth-inning grab by Peralta on a Tommy Pham liner, the Padres might be 3-0 for the first time since their 1984 pennant-winning campaign.)

“We regroup, get some rest this evening and do it again tomorrow,” Tingler said. “A chance to win the series.”

Rotation ‘pitching with our hair on fire’
Tingler noted that he would’ve felt comfortable giving the No. 1 spot in the rotation to any of his three starting pitchers this weekend. They certainly all pitched like Opening Day starters.

After Chris Paddack and Dinelson Lamet baffled D-backs hitters on Friday and Saturday, respectively, Garrett Richards followed suit. He worked five scoreless frames, allowing just a hit and three walks while striking out six.

“I don’t think teams are going to be very excited to come in here and catch us three,” Richards said. “We’re pitching with our hair on fire, and we’re ready to go. We’re out there to win, and these young kids, man, they’re super talented, and they work hard.

“There’s only even better things to come. It’s very, very exciting right now. I feel like we’re just touching the surface.”

The trio of Paddack, Lamet and Richards combined for 16 innings of one-run ball this weekend with 18 strikeouts. But Paddack and Lamet were given a bit more leash than Richards, who was lifted after just 73 pitches.

Richards, who made three starts late last season after recovering from Tommy John surgery, said he understood the decision. He’s been eyeing this season ever since he signed his deal with the Padres, post-surgery in 2018. And in his first start, he looked like vintage Garrett Richards.

“I’m having fun playing baseball again,” Richards said. “It’s not rehab anymore. … It just feels good to be back out there, pitching and pain-free.”

Big spot, first hit
Tingler called on utility man Jake Cronenworth for his big league debut with the Padres trailing by a run in the eighth. He pinch-ran for Hosmer, who had worked a leadoff walk. Cronenworth smartly tagged and went to third base on a deep fly ball from Jurickson Profar, before scoring on Garcia’s game-tying single.

Of course, when Cronenworth pinch-ran, Tingler gambled that Hosmer’s spot in the order wouldn’t come up again. With two outs in the ninth -- and Cronenworth as the tying run -- it did.

Cronenworth, the team’s No. 17 prospect, delivered anyway. He laced a hanging Archie Bradley curveball into the right-field corner for an RBI double, cutting Arizona’s lead to one. But two pitches later, Cronenworth was left stranded at second when Wil Myers tapped back to the mound to end the game.