SAN FRANCISCO -- Take your pick of the Phillies’ biggest unforced error, missed opportunity, or common mistake in Friday night’s 5-3 loss to the Giants:

♦ The fly ball that got center fielder Odúbel Herrera twisted around for a leadoff double and the two-out line drive that deflected off first baseman Rhys Hoskins’ glove and went into right field for an RBI double in a three-run second inning.

♦ Bryce Harper misread three balls that he put in play, including getting thrown out at second base trying to stretch a single off the left-field wall in the sixth inning after appearing to not run hard out of the box.

♦ Vince Velasquez’s two-out walk of Giants pitcher Johnny Cueto with the game tied in the fourth inning.

Considering Cueto was 0-for-13 with five strikeouts this season -- and hadn’t drawn a walk since 2017 -- Door No. 3 has to be your winner, especially after Wade followed by smashing a triple off diving Herrera’s glove to drive home Cueto and snap a 3-3 tie.

“Walking Cueto, that’s just unnecessary,” Velasquez said. “Cueto’s not going to get on by bunting or hitting, so in a sense, I have to get that guy out. It’s just a mandatory out. It seemed like I was all over the place today.”

The Phillies played a sloppy game all around in losing the opener of a three-game series to Gabe Kapler’s National League-leading Giants and falling back below .500 at 33-34.

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In particular, the second inning was ugly, as the Giants grabbed a 3-1 lead. It all began with Herrera’s misplay of Brandon Crawford’s leadoff double, a play that manager Joe Girardi labeled “a tough read early in the game.”

“But yes,” Girardi added, “he’s capable of making that play.”

If Hoskins caught LaMonte Wade’s line drive, which turned into an RBI double to right field, Velasquez may have gotten out of the inning with minimal damage. But Velasquez also threw a wild pitch in the inning and another pitch that was charged as a passed ball to catcher Andrew Knapp.

“It’s a good Giants team over there right now. They’re playing well. They’re swinging it well,” Harper said. “We can’t give them outs. You get 27 of them. We’re giving them a couple more. We need to be better tomorrow and make less mistakes.”

But Velasquez didn’t help matters either. He threw only 45 strikes out of 84 pitches and gave up four hits and four walks in four innings. The Phillies had to use rookie left-hander Bailey Falter, penciled in to come in behind Spencer Howard on Sunday.

Now, it appears the Phillies will have to alter their plans.

“We might make a change,” Girardi said. “We’ll see.”

Harper’s baserunning misadventures

Harper returned to the lineup after leaving Tuesday night’s game in Los Angeles with back spasms and sitting out Wednesday night. And he had an eventful game on the bases.

In the first inning, Harper thought he lined out and didn’t hustle to first on a ball to shortstop Brandon Crawford that turned into a double play. In the third, he hit a fly ball that he thought was going foul before it came back into play and landed in shallow left field. Again, he wasn’t running hard and wound up with a single.

“I’ve never seen that before, actually,” Harper said. “Man, it was in the stands. I was watching, watching, and I was like, ‘Oh man, that ball’s coming back.’ Got caught right there and need to be on second base, of course. I need to be better.”

But the most costly play came in the sixth inning. Harper hit a ball off the top of the left-field fence and may have admired it for a few seconds. He tried to leg out a double but got thrown out by Wade.

“I thought he just made a really good throw,” Harper said.

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Knapp injured

Knapp will be placed in the seven-day concussion protocol after getting square hit in the mask by a pitch from Falter in the sixth inning.

The ball knocked Knapp to the ground. He remained in the game initially, but was replaced by J.T. Realmuto. The Phillies will call up Rafael Marchán from triple-A Lehigh Valley before Saturday’s game.

Leading man

Herrera led off for the 14th time in 15 games and hit Giants starter Johnny Cueto’s fourth pitch over the fence in straightaway center field. It marked his second career leadoff home run.

The Phillies’ other runs came on Andrew McCutchen’s homer in the fourth inning. McCutchen has five homers in June.

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Up next

Aaron Nola (5-4, 3.69 ERA) will attempt to build on 7 2/3 scoreless innings last Sunday at home against the Yankees. He’s 0-2 with an 8.78 ERA in three career starts at Oracle Park. Left-hander Alex Wood (6-3, 3.71 ERA) will start for the Giants.