SAN FRANCISCO — Asked Thursday afternoon if he was more curious about Chris Marrero’s defensive or offensive adjustment to AT&T Park, manager Bruce Bochy said “both.”

Well, consider all the boxes checked off. Marrero had his best defensive game of the spring, easily handling a few routine flies to left and robbing Jaff Decker of a single with a diving grab. He doubled in two at-bats and came within about six feet of adding a solo homer.

“He made a nice catch coming in and made all the plays,” Bochy said. “He had a couple of good at-bats. It was a good game for him. The first time here in left field, and it’s not an easy left field, he looked comfortable. He looked relaxed. All those things.”

Marrero’s shaky spring work in left was the only hole in an otherwise sparkling resume. He got tested twice in the early innings under new lights at AT&T Park, catching a pair of routine fly balls. He cut off a ball to the left-center gap and also ran down a Stephen Vogt liner. Decker’s flare in the fifth was snagged an inch before it touched grass. The only blemish was a throw to the wrong base, over the cutoff man.

After hitting eight homers in Arizona, Marrero came a few feet from hitting one off the left field pole in his first at-bat. He ended up striking out, but he drilled a ball into Duffy’s Corner in his second at-bat, getting a double.

Bochy still would not name Marrero to the Opening Day roster after the game, but he did note that the stakes have been raised for that spot. The Giants will have a platoon in left after originally saying they wouldn’t. They never intended on platooning Jarrett Parker and Mac Williamson, but Parker will platoon with a right-handed bat, seemingly Marrero. Williamson will miss the start of the season with a strained quad.

“I didn’t want to get into a platoon with (Parker and Williamson) because that’s not where a platoon makes sense,” Bochy said. “Williamson, he hits righties better than lefties. Plus you’re slowing down (Parker’s) development. It’s different with the guys we have.”

If Marrero does win that job, he’ll get a couple of early starts. The Diamondbacks will throw Pat Corbin and Robbie Ray at the Giants during the season-opening series.

--- The fifth starter competition appeared to be over when Ty Blach took the mound for the seventh, two days after Matt Cain threw 99 pitches. Not so fast, Bochy said. Any announcement will wait until Friday. Bochy said Blach simply needed some work. He last pitched March 26, throwing six innings.

If the Giants do name Cain the fifth starter and cut Blach down to a short-stint role, that last spring start will prove valuable. He got stretched out, and he should be ready to enter the rotation at any time.

--- George Kontos has seven consecutive strikeouts and 18 in 10 innings this spring. The Giants have always been hesitant to give him a bigger role because he doesn’t have the traditional late-innings repertoire, but at some point, results are results. He wants a bigger role, and given how he’s looked the last couple weeks, maybe it’s time to see if he can be the right-hander version of what Will Smith would have been.

--- Mark Melancon’s first outing at AT&T Park: two strikeouts, groundout. #NotTorture

--- The Giants announced a crowd of 39,380. The sellout streak doesn’t include exhibition games, but it’s going to be hard to keep that going this year if this team goes through a skid.

--- The new LED lights at AT&T Park certainly changed the look. The field looked a little darker to my eye, but team officials insisted that wasn’t the case. There’s no denying, however, that the stands are significantly darker. I can see fans grumbling once the season starts. Giants people I talked to viewed it as more of an “indoor arena” look, with everything centering on the action on the field.

--- Brandon Belt shook his head and smirked when his first swing at AT&T Park this season resulted in a long fly ball that died in front of the left-center wall.

“Welcome to SF!” he joked later. “It was like, well, that goes out in Arizona.”

--- Brandon Crawford’s postgame victory soundtrack kicks off with “The Humpty Dance” this season. Strong.