ATLANTA -- It's not a platoon, per se, because Tommy Pham and Trent Grisham are still the Padres' everyday starters in left and center field, respectively.

But since the All-Star break, the righty-hitting Pham and the lefty-hitting Grisham have essentially served as a platoon in the leadoff spot for the Padres, who are using left-right matchups to dictate who will set the table for the fearsome middle of their lineup.

Since they returned from the All-Star break on Friday, the Padres have constructed lineups for two righties and two lefties (counting Atlanta left-hander Kyle Muller on Monday night).

Pham led off against both lefties, Grisham against the righties. The other has dropped below the Padres' 2-3-4 of Fernando Tatis Jr., Jake Cronenworth and Manny Machado.

"They're versatile, as a lot of our hitters in our lineup are," Padres manager Jayce Tingler said of his two leadoff options. "We're able to lengthen our lineup, give us some left-right, right-left, different kinds of matchups."

Both Pham and Grisham fit the prototype of a leadoff hitter. They’re two of the best in baseball at it. They work counts, they reach base at a high clip, and they're excellent baserunners.

Most teams would be thrilled to have one player like that atop their lineup. The Padres have two. (Finally.)

Early in the season, Grisham served as the team’s leadoff man, but Pham struggled to put things together after a rough offseason, health-wise. When Pham began to heat up, Grisham sustained a heel bruise and missed a month.

At long last, they're thriving at the same time, and the Padres have chosen to alternate the leadoff spot as a result. That doesn't mean the roles of Grisham and Pham change all that much though.

"I expect those guys -- whether it's Grish, whether it's Pham, whether they're hitting one, five, seven -- I want them to have their same at-bats," Tingler said. "Don't go: 'Hey I'm in the five hole, I've got to do damage here.' No. ... Wherever they are, I want them to have the same approach."

New role for Lamet?
Right-hander Dinelson Lamet is progressing slowly toward a return from right forearm inflammation -- and he might be progressing toward a slightly less taxing role when he rejoins the Padres' pitching staff.

"The best opportunity to get him through the year healthy, and possibly the best opportunity to help this team, it may be in shorter stints going forward," Tingler said.

Does that mean a setup role? Does that mean a long-relief role? Does it mean a piggyback with left-hander Ryan Weathers, who is also recovering from injury?

Those are questions for another day, Tingler said. First and foremost, the Padres need to get Lamet healthy. This is his third stint on the IL this season -- after his excellent 2020 campaign came to an early end because of a strained right UCL.

Lamet has thrown a light bullpen and will throw at least one more, possibly two, on this road trip before facing hitters. He's then likely headed for a rehab stint, and if all goes well, an August return might be in the cards.

In what role, exactly? That's TBD.

Mateo's value in focus
Since his arrival in San Diego, it seems, Jorge Mateo's place on the Padres' roster has been tenuous. And yet, here he is, a season and a half later, playing sparingly, yet finding a way to make an impact on the bases.

An elite speedster, Mateo was called upon as a pinch-runner in a one-run game in the ninth inning on Sunday, and he swiped both second and third base, before scoring the tying run on Grisham's two-out single.

In that spot, Mateo said, he typically knows in advance that he's a pinch-running option. He gets loose in the tunnel next to the dugout, while also poring over data on the opposing pitcher's tendencies.

"I always need to be ready for that moment," Mateo said. "And I need to prepare myself accordingly. … I need to get my mindset in that situation that I’m going to be running.”

Mateo has struggled at the plate, but the Padres see huge value in his baserunning -- especially in the context of postseason roster construction.

That's not to say Mateo's spot is secure. The Padres are looking for bench upgrades on the trade market, and Mateo is hitting just .200/.244/.318 in 91 plate appearances. He'd likely have spent several stints in the Minors this season were he not out of options.

Still, with the Padres in the midst of a tense NL West race, they’re going to be playing some crucial games down the stretch against the Dodgers and Giants. They also have more off-days in the second half, meaning the last few places on their roster can be used less for attritional purposes and more for a unique role player like Mateo.

"I'm just trying to be 100 percent prepared and concentrated on being able to help the team with whatever they ask for," Mateo said. "It's the second half now, we're trying to win games, and the games are getting more important, and I'm just trying to be as concentrated as possible when that moment shows up."