SAN DIEGO -- Rookie Dinelson Lamet knew his slider wasn't right. He went about fixing it before facing Pittsburgh on Saturday night and the results are in: Padres 4, Pirates 2.

"It's something I've been working on since my bullpen because I knew I hadn't been in the zone with it the last time," Lamet said through a translator. "I felt much better than I did against San Francisco in my last outing with that pitch. I had much more command, much more control."

Using his fastball and slider, the right-hander threw six-plus solid innings and Manuel Margot homered as the Padres won their fourth straight game.

Lamet (5-4) allowed two runs and two hits, struck out seven and walked two while winning his second straight start while throwing a career-high 104 pitches.

"He did a great job," Padres manager Andy Green said. "He was around the zone for most of the game. He didn't have pinpoint control. but that's not what we look for in him. It's stuff over location."

Relievers Craig Stammen, Phil Maton and Kirby Yates finished off the fading Pirates, who lost their fourth straight and sixth in their last seven games as they fell to 2-6 on their nine-game road trip.

Yates worked a spotless ninth for his first save of the season and second of his career. With Brandon Maurer traded to the Kansas City Royals and Brad Hand unavailable after four straight saves, Green turned to Yates.

Pirates manager Clint Hurdle said his offense couldn't flip their script with Lamet.

"He had a good slider," Hurdle said. "Unfortunately, the ones that were in the zone we weren't able to do much with."

Ivan Nova (10-8) lasted five innings, surrendering four runs and eight hits with six strikeouts.

"It's been a little bit of a rough stretch for him," Hurdle said. "However I do think he's tracking back in the right direction."

Nova didn't sound discouraged after the outing.

"I was throwing really well the whole game," he said. "I had a good handle on the ball, but I was just missing my location, and the location is really important."

Pittsburgh pulled within 4-2 in the seventh, when it chased Lamet and treated Stammen rudely. David Freese had an RBI single off Stammen after Lamet hit Andrew McCutchen with a pitch and walked Josh Bell. The other run arrived on Francisco Cervelli's double-play grounder.

Margot produced his eighth home run of the season in the fifth, a solo shot to give the Padres a 4-0 edge. During the homestand, he is 12-for-24 with a double, a triple, three homers and six RBIs.

Lamet opened with four hitless innings as he allowed only a walk to Josh Harrison, the game's second batter. But in the fifth, Freese and Adam Frazier smoked singles to right with no outs.

The rally died when Cervelli lined out to Carlos Asuaje and he doubled Freese off second base. Jordy Mercer lifted a soft fly to left to end the inning.

San Diego built its lead to 3-0 in the fourth. Hunter Renfroe walloped a double to score Cory Spangenberg, after he led off with a single.

The Padres got to Nova early, scoring twice in the first inning. Jose Pirela had the first of his two triples, this one chasing in Margot after he opened with a single. Pirela scored on Hector Sanchez's double.

"He's been hitting the ball hard since he got here," Green said of Pirela. "He's been a huge part of what's we've been able to do this last month and change. You look up and he's always in the middle of everything."

It was the 16th time in club history that a Padres player had two triples in a game.

NOTES: Pirates OF Gregory Polanco (hamstring) continues to make strides as he took batting practice and did defensive drills before the game. ... Padres 1B Wil Myers was out of the starting lineup and won't be in it Sunday, either. Myers has been scuffling as he is mired in a 16-for-94 stretch. ...C Austin Hedges (concussion) and INF Yangervis Solarte (oblique) are expected to be activated for Sunday's game.