SAN DIEGO -- Fresh off a grueling back-and-forth three-game series with the Rockies, the D-backs were a tired bunch Thursday when they opened a four-game set against the Padres.

Two of their better hitters were out of the lineup, with Lourdes Gurriel Jr. battling a sore hip and Ketel Marte getting a day off after three games at altitude where he has had issues in the past.

Their bullpen was on fumes with closer Paul Sewald, Kevin Ginkel, Miguel Castro, Tyler Gilbert and Bryce Jarvis unavailable after their recent workloads. Despite all that -- and the fact that the Padres hit the ball hard throughout the game -- the D-backs managed to come away with a 3-1 win, their third victory in a row and fifth in their past seven games.

• Box score

The D-backs also picked up a half-game in the National League Wild Card race, moving one game out of the final postseason spot in a crowded field.

“To be honest, we were gassed,” D-backs manager Torey Lovullo said. “I know this group was very tired coming out of altitude and Colorado, and I keep making a big deal about that because it's real. This was a fatigued team today that went out there and won a baseball game, and that's what I'm most proud of.”

Zac Gallen didn’t feel at his best, and the Padres made a lot of loud contact against him, but those balls found gloves. Gallen allowed just one run and three hits over 6 1/3 innings to continue his push for the NL Cy Young Award.

Gallen (13-5, 3.17 ERA) was sitting at 97 pitches through six innings when Lovullo asked him if he could give him just one more batter -- the right-handed-hitting Xander Bogaerts -- to open the seventh.

“I told him I could get him one [more] out,” Gallen said.

Gallen did, and that allowed Lovullo to match up left-on-left with Kyle Nelson and Jake Cronenworth.

After Nelson got the first two outs of the eighth, Lovullo turned to one player who wasn’t with the team in Denver -- Justin Martinez.

The flame-throwing rookie right-hander had been called up from Triple-A Reno on Wednesday night, arriving in San Diego the early-morning hours Thursday.

As he jogged in from the bullpen, the 22-year-old who dreams of being a big league closer did not realize he was in line for his first career save.

“My main focus was just to execute my pitches and not think about the outcome,” Martinez said. “And then when I went into the ninth, I didn’t even think about it. I just kept focus on executing my pitches.”

After striking out Ha-Seong Kim on a 102 mph four-seamer to end the eighth, things got a little dicey for Martinez in the ninth when he walked Fernando Tatis Jr. on four pitches to open the inning.

Later in the frame with two outs and two on, Martinez froze Cronenworth on a split-finger fastball to end the game.

Lovullo was asked after what led him to trust Martinez -- who had allowed five runs in one-third of an inning against the Reds last month and was optioned to Reno following that game -- in such a big situation.

“We had to,” Lovullo said. “I felt like it was his opportunity, his day to shine. And he's been throwing the ball really, really well [in Reno]. We were very thin in the bullpen and the reports from player development were he's ready for this opportunity. So with Sewald down I thought it was a great opportunity and a great response.”