SAN DIEGO -- Merrill Kelly had the shortest outing of his budding Major League career, lasting only 1 2/3 innings in the D-backs’ 5-2 loss to the Padres on Wednesday afternoon at Petco Park.

What Kelly takes away from his abbreviated workday will go a long way toward determining his fortune in many games to come.

Kelly was hit hard in his 10th big league start. There’s no getting around that. He faced 14 batters and walked four of them. Of the 10 balls put in play, eight came off the bat with at least a 95.7-mph exit velocity.

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“Just forget about it,” Kelly said. “It’s over with. There’s nothing I can do now. I can’t go back and make pitches. It’s over and done with. Just try to focus on the next start.”

The D-backs could take a similar attitude about the team as a whole. The more forward-thinking they are, the better. The recent past and the right now don’t offer a whole lot to boost their confidence.

On the wrong end of a three-game sweep by the Padres, the D-backs suffered their fifth straight loss and fell to .500 (25-25). Arizona slid to third place in the National League West, a game behind second-place San Diego.

When play wrapped up May 4 and sports fans were debating the merits of the Kentucky Derby disqualification, the D-backs were holding the second-best record in the NL at 20-13 and were only a game behind the first-place Dodgers. They are 5-12 since.

“We got off to a good start to the season,” shortstop Nick Ahmed said. “That allows you to handle a stretch like this and still have a good season. We’re going to bounce back.”

Arizona has some hurdles to clear before any bouncing back can happen. Consider:

• The team has no answers about how long left fielder David Peralta’s right shoulder soreness will last. That’s a big bat erased from an offense that has produced only 12 runs during the losing streak.

• Infielder Wilmer Flores’ right foot injury turned out to be a broken bone. He’ll be out longer than the 10-day minimum stay on the injured list.

• The D-backs are reaching back to Triple-A Reno to plug a hole in the rotation. Right-hander Taylor Clarke will go Saturday at San Francisco, manager Torey Lovullo said.

• The roster is in flux. Reliever Jimmie Sherfy was optioned to Reno after throwing 2 1/3 innings in relief of Kelly on Wednesday. Arizona has been short-handed on the bench between carrying 13 pitches and the injuries. Might Minor League home run leader Kevin Cron (21 dingers at Reno) get his first big league call?

“We’ve got to find a way to make it better, no doubt about it,” Lovullo said. “We’re frustrated. You know, this game’s hard. But this is a very talented group.”

Kelly’s frustration was partnered with physical pain. The hardest-hit ball against Kelly actually struck him. With one out in the second inning, Franmil Reyes walloped a curve for a grounder at 110 mph off the bat. The ball caromed off Kelly’s right foot for an infield single. The right-hander took several warmup throws before staying in the game. But after a hard-hit sacrifice fly and two walks, Kelly was pulled by Lovullo.

After the game, Kelly said the foot is sore but otherwise OK.

Kelly, a 30-year-old rookie who spent the previous four seasons pitching in South Korea, threw 34 pitches in a three-run first inning and another 29 while getting two outs and allowing another run in the second. His final line: four runs, five hits and the four walks.

“I just didn’t do my job,” he said. “Coming off four losses in a row, it would have been big for me to give a quality start. I wasn’t able to do that. I wasn’t able to locate fastballs, cutters -- really, pretty much everything.”

Kelly (4-5) has four quality starts and tossed 5 1/3 scoreless innings vs. the Giants his previous time out. He has shown he can compete with Major League hitters. Lovullo will be watching closely to see how Kelly reacts to an outing with few positives, how he prepares for the next start.

“Give us feedback, allow us to respond to that feedback and be coachable,” Lovullo said about what can be done to move forward off a bad start. “[Pitching coach] Mike Butcher saw a couple things that needed to get better after the first inning, and, unfortunately, it didn’t happen.

“Pace, tempo, attacking -- those things were very identifiable. You can talk about game plan and preparation all you want, but it’s about execution.”