Gregor Blanco smiles as he takes batting practice during a workout Monday. (Jeff Roberson/AP Photo)

On the eve of the World Series, Gregor Blanco still beamed at the mention of the Giants’ opponent in the first round of the playoffs. He had taken extra satisfaction in knocking out the Nationals, and he did little to hide it. “Yeah,” he said, covering his mouth as he laughed. “Yeah.”

Blanco found motivation – “huge,” he said – to beat the Nationals because he had played in their organization, and been cast aside, before launching his career with the Giants. He has become a postseason mainstay this year, leading off and playing center field in place of injured Angel Pagan. In the World Series, Blanco is 4-for-20 with five walks, a home run to lead off Game 2 and a handful of terrific catches.

Blanco has been a key part of the Giants’ success since 2012, after his brief tenure in the Nationals organization. The Nationals picked Blanco off waivers from, coincidentally, the Royals in 2011 and assigned him to Class AAA Syracuse.

Despite a .201 batting average at Class AAA, Blanco posted a .350 on-base percentage. His ability to reach base impressed the Giants scout who monitors the Nationals’ farm system, San Francisco assistant GM Bobby Evans said. Still, Blanco’s playing time dwindled at Syracuse.

“I don’t know what happened,” Blanco said. “I was in a situation in my career, I’m always a guy that when things are not going the way they are supposed to be, I build myself stronger. I was in Syracuse. I played the first week. I stole a bunch of bases in one week. My bat wasn’t good. I cannot say what happened. I found myself not playing, on the bench.”

Blanco also played through a sore hand, and he learned he had broken his hamate bone, an injury that required a relatively minor surgery. With a month left, “They just told me, ‘You’re not going to play with us anymore. You can go home if you want,’” Blanco said. Blanco decided he would have the surgery on his own dime, recover and try to catch on with a new team. The Nationals informed him they would not sign him.

The Giants continued to track him when Blanco played winter ball, and “several [scouts] commented on his ability,” Evans said. The Giants beat out two other teams for Blanco because they offered Blanco the best opportunity to make the team. But nothing was guaranteed – Blanco entered spring training on a minor league contract.

“He’s one of the few guys that, within a week or two of camp, he had already made the club,” Evans said. “It was just that obvious.”

Blanco started the year on the Giants’ bench, and by the end of the season he had become their everyday left fielder. In the playoffs, batting seventh, he reached base at a .339 clip with a homer, two doubles and two triples. Blanco moved to center field this season when Pagan went down, and even there the Giants valued his defense as much as his offense.

“There could be such a long highlight reel just of his postseason catches,” Evans said. “His defense has been such a breath of fresh air. The way he saves the game and saves the pitching staff, that’s been him at his best.”

In the first round, hitting leadoff in the postseason for the first time against the Nationals, Blanco placed added pressure on his performance. He kept telling himself he had been a leadoff hitter his entire life, that he had dreamed of this moment, and after the path he took to get to the Giants, it had finally come. He told himself, “Play the game and be the guy.”

“And since then, I’ve been doing it,” Blanco said. “I’m really having fun. It’s enjoyable. And why not? This is the World Series, so I should have fun.” ​

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