CHICAGO -- If the Giants miss the playoffs this season, this three-game series against the Cubs will be one that they remember. San Francisco dropped Thursday afternoon’s series finale to Chicago, 1-0, at Wrigley Field.

The Giants fell to 6 games behind the Cardinals for the second National League Wild Card spot following the three-game sweep.

“We knew how important these games were. That makes it even tougher,” Giants manager Bruce Bochy said. “These were critical games for us. [The Cubs have] been good at home. They find a way to win, and they did that against us. This was a tough series for us, because it was an important series.”

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The series against Chicago presented a new reason for frustration in each game, and after coming up short in Wednesday’s 12-11 slugfest, the Giants were unable to finish on top in Thursday’s pitchers’ duel.

Jeff Samardzija was excellent against his former club. Samardzija was perfect through his first three innings before allowing a hit in the fourth. He allowed just one run on two hits over his seven innings, striking out four and walking one. The 34-year-old right-hander has a 2.00 ERA in 10 starts since July 1.

“It’s a great story, what he’s done, how consistent he’s pitched. He and Bum, they are workhorses,” Bochy said, referring to ace Madison Bumgarner. “He’s done a great job of keeping us in the game.”

But a costly error by shortstop Brandon Crawford led to a two-out RBI single from Anthony Rizzo, which proved to be the difference in Samardzija’s outing.

For a team like San Francisco that's hanging on to its postseason hopes, making your own luck is imperative.

“I think we missed an opportunity, but I don’t think it’s crippling,” Samardzija said. “There’s a lot of baseball to be played. I think we’ve shown here over the last couple of months that if we hang around and play some good ball, we get hot and usually go on a nice run.”

There would be no better time to get on that run than right now, as the Giants head back to the Bay Area for a two-game series against the rival A’s over Players’ Weekend before facing off against two teams in the middle of the National League Wild Card hunt in Arizona and St. Louis.

The D-backs are ahead of the Giants in the NL Wild Card standings by one game, and they come to San Francisco for two games next week. The Giants meet the Cardinals, who hold the second NL Wild Card spot, in a big four-game set to start September.

“We’re in a tough place on a tough road trip. I thought we battled and played hard the last few games, but they just didn’t turn out for us,” Samardzija said. “We’ll go home try to start another hot run. You can make up ground quick if you win five or six in a row.”

Giants wait for news on Sandoval

The Giants will not know what the status of Pablo Sandoval’s ailing right elbow is until Saturday, Bochy announced after the game.

Sandoval met with orthopedic surgeon Dr. Neal ElAttrache in Los Angeles on Wednesday to get a second opinion on his elbow. The 33-year-old infielder was placed on the 10-day IL on Aug. 14, retroactive to Aug. 11, with right elbow inflammation.

Sandoval received a cortisone injection on Aug. 11, but he hadn’t seen much improvement since. He was in the middle of a bounceback season, and he had been a steady presence in San Francisco’s lineup, hitting .269 before landing on the IL. His 14 home runs and .823 OPS are his highest since 2014, during his previous tenure with the Giants.