MIAMI -- On Monday night at loanDepot park, fans were treated to a battle of two All-Star pitchers. And while a pitchers’ duel was expected to be the story of the night, despite Joe Musgrove having faded some from the NL Cy Young conversation over the past two months as Miami ace Sandy Alcantara strengthened his own stock, it was a play in the outfield that stole the spotlight in the Padres’ 3-0 series-opening loss to the Marlins.

Musgrove allowed three runs on eight hits with five strikeouts over six innings -- his 17th quality start this year. His performance, albeit not his best, kept San Diego in the game even when the offense’s power was lacking (just four singles through eight innings). Musgrove even shook off Bob Melvin when the manager came out to retrieve the starter, who had thrown 107 pitches and had the bases loaded with two outs in the sixth inning. Musgrove then struck out Peyton Burdick on five pitches for 112 pitches, two shy of his career high.

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But it was a play earlier in the inning that drew attention, when left fielder Jurickson Profar was slow to throw in a ball Miguel Rojas hit off the wall in left-center.

Profar has played outfield at loanDepot park three times, all last season. There are countless possibilities for why Profar didn’t move with more alacrity to throw the ball in. The left fielder didn’t give an explanation for the play postgame, though he did take ownership of the play.

“I just had to throw it in,” Profar said. “I made a mental mistake right there. I just, it happened, and I take full responsibility for it. And it won't happen again.”

To his skipper -- and what is the most likely explanation -- it seemed that Profar was trying to motion to Ha-Seong Kim for a cutoff throw.

“I think he was trying to motion Kim to get in a cutoff position,” Melvin said. “I believe that's what happened, and then [he] just took too long and didn't get thrown in there in time.”

Even Rojas, who had slowed down as he approached second base but saw Profar holding the ball and motored to third for a triple, noticed the Padres didn’t have a cutoff man in position.

“I don't really know what happened,” Rojas said. “I just saw that he was doing some kind of motion over there. … I watched the replay after and I don't know if he was like [motioning that way] to me or to his shortstop. I don't know. I'm just glad that it worked out, and I made it to third base.”

Rojas scored in the next at-bat via a single from catcher Jacob Stallings, giving the Marlins a 3-0 lead they held for the final three innings. As Musgrove said postgame, that third run made it even harder for the Padres, who were hitless in the seventh and eighth.

“The extra run in the sixth doesn't help,” said Musgrove, who also acknowledged his own mistake: an 81.1 mph curveball right down the middle that JJ Bleday hit out of the park in the second. “If you're facing Sandy, you’ve got to be damn near perfect. So just not good enough today.”

When the Padres returned to the dugout after Musgrove retired Burdick, a few teammates approached the left fielder. Television cameras picked up third baseman Manny Machado, right fielder Juan Soto and Musgrove talking to Profar at the far end of the visiting dugout.

Soto said that they were offering Profar some support.

“We [were] just trying to help him out,” Soto said, “and no matter what's going on on the play, just keep playing baseball. Sometimes, we feel down, we feel uncomfortable with it. But we just got to keep playing baseball. We’re humans, we make errors.”

Musgrove acknowledged his emotions afterward.

“I was a little frustrated,” he said. “Saw [Rojas] pulling up for a double, and maybe he just took a chance at challenging. Pro has been great out there all year. And I don't mean to make it sound like [Profar’s] baiting guys into running and stuff. But, I mean, maybe our relay guy was a little out of position. [Profar] told me he was waiting for [Kim] to get over in position and thought he got rid of [the ball] with enough time to hold [Rojas] from going.

“It's frustrating at the time being, but you know, Profar is not a lazy player, by any means. Mistakes happen, and I know it won't happen again.”