SAN DIEGO -- Joey Lucchesi had another strong outing, but his only reward was a series of back slaps. The Padres fell to the Pirates, 5-3, despite Lucchesi’s solid performance on Friday night at Petco Park.

“Yeah it kind of sucks a bit,’’ Lucchesi said. “But you have to stay positive and keep going because it’s a long season.’’

Lucchesi’s stint was anything but short. He tied a career-high by working seven innings as he allowed two runs on five hits. His six strikeouts with no walks only added to his excellence.

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“We feel really good at where he’s at,’’ manager Andy Green said.

Where Lucchesi (3-3) hasn’t landed of late is in the winner’s circle. He surrendered only a run in his last start against the Rockies, lasting 5 1/3 innings in a no-decision.

It was a no-brainer as to why the southpaw was so keen against the Pirates. Lucchesi was deploying his two-seam fastball in on the hitters and then working away with his cutter. That set up his funky “churve” pitch, which causes swings that often miss the bat.

“He’s got a lot of weapons to choose from,’’ catcher Austin Hedges said. “But the most impressive thing is he’s figuring out how to get quick outs, too, and not strike everyone out. That’s how we get to pitch into the seventh.’’

It wasn’t easy facing the Pirates’ Jordan Lyles (4-1) as the former Padre struck out a career-high 12 batters. San Diego managed but five hits against him in losing for the fifth time in seven games. One of its knocks was Franmil Reyes’ team-high 14th homer.

“We didn’t have great at-bats against [Lyles],’’ Green said.

Reyes was the exception. He struck quickly with a first-inning, 420-foot blast in staking the Padres to a 1-0 lead. It was Reyes’ second homer in two days and his fourth in five games.

But other than that Lucchesi’s start was derailed by an offense that scuffled until Ty France added a two-run long fly in the ninth.

The Padres squandered an opportunity in the sixth when Eric Hosmer singled with one out after Manny Machado doubled to extend his hitting streak to 10 games. But Wil Myers was caught looking on a slow curveball and France flied to center to end the threat.

“When you put yourself in that situation, that’s when you have to cash in,’’ Green said. “That changes the trajectory of the game.’’

Lucchesi’s arrow continues to point up.

“I’m trying to better myself every single day and push myself,’’ he said. “Tonight we were attacking both sides of the plate and we were doing that really well to keep them off balance.’’

Lyles was in the opposing dugout last year, watching Lucchesi navigate through his rookie year. The Pirates’ righty is impressed with how his ex-teammate has developed.

“Plenty of talent and he’s a good dude,’’ Lyles said. “He looked in my direction for a handful of things, on and off the field last year, and I was happy to help him.’’

Lucchesi had one hiccup and it was costly.

The Pirates forged ahead in the fourth when Bryan Reynolds didn’t bite on two changeups outside the zone and then demolished Lucchesi’s 89 mph sinker for a two-run shot. Josh Bell was aboard on a sharp single that skipped past Hosmer, giving the Pirates a 2-1 edge.

“It was a down-and-away fastball and I missed down the middle,’’ Lucchesi said. “That was my one mistake.’’

That misguided offering aside, Lucchesi did his job.

“For him to go seven innings, save our bullpen and have us in a position to win the game, that is what good starting pitchers do,’’ Hedges said.

Lucchesi is doing just that.