CHICAGO -- We've seen this act before.

Chicago Cubs reliever Travis Wood is called into duty at the spur of the moment and helps save the day. This time it was his arm and bat which secured the Cubs a 5-2 victory on Saturday night and a commanding 2-0 series lead in their National League Division Series matchup with the San Francisco Giants.

Wood didn't play left field, as he did earlier this season, but he did hit a ball over the left fielder's head in the fourth inning for a solo home run, returning the momentum to the Cubs after the Giants had seemingly captured it.

"I did put him in there because as he was coming up (to bat) second, that was part of it," manager Joe Maddon said after the victory. "Did not want to pinch hit there obviously with the two lefties at the top of the batting order (of the Giants), I thought it was a good spot for him."

It was a great spot as Wood did his job -- and then some. After the Cubs jumped out to a 4-0 lead the Giants made starter Kyle Hendricks look human for a moment, scoring twice in the third inning. Then came the scare of the early postseason, as Hendricks had to leave the game after taking a line drive off his pitching forearm. That could have been the Giants' chance to climb back into the game and series -- until Wood picked up a bat.

"It happened pretty quickly," Wood said of entering the game after Hendricks left. "It always does in a situation like that. As a bullpen guy you're always prepared, especially with Joe, for any situation -- anything that pops up -- so you kind of keep your body and your mind locked into the game. So I was ready to come in. And then the at-bat, it was just, I figured he [George Kontos] was probably going to start me out with a cutter, and I made a good swing on it and was fortunate enough to get him and hit it out of the park."

Astonishingly, the home run was the first by a reliever in the postseason since 1924. Like Javier Baez's long ball the night before in Game 1, Wood ignited the crowd and his teammates, especially his fraternity brothers down in the bullpen.

"It was by far one of the best things I've seen so far," reliever Carl Edwards Jr. said. "Then he goes out and puts up a zero, and it was like 'Hey, you’re job is done. You're done. Go home now.' It was exciting in the bullpen to see that, and it gave us an extra boost."

Standing at his locker, Edwards nodded over to bullpen catcher Chad Noble.

"He called it," Edwards said of Noble. "He said Wood would hit a home run."

Noble confirmed the prediction.

"I told those guys, watch this," he said as he waved his finger making the home run sign just as an umpire would.

Considering that since 2010, Wood's 2.9 percent home run percentage is actually higher than Giants slugging pitcher Madison Bumgarner (2.7), maybe Noble's prediction wasn't all that impressive. After all, it was Wood's 10th career home run in the big leagues.

Wood set the tone for what was to come when he returned to the mound: 5 1/3 scoreless innings spread out between five relievers. His home run took the wind out of the Giants' sails -- if there was any to begin with -- then Edwards, Mike Montgomery, Hector Rondon and Aroldis Chapman did the rest.

Perhaps the most amazing stat of the first two games of the series is that the Cubs haven't issued a single walk. It's one thing when Cy Young candidates Jon Lester and Hendricks deny the opposition free passes, but five different relievers? That’s hard to do.

"And then you could talk about the whole group -- CJ, outstanding," Maddon said. "And Montgomery, you know, very, very good. The curveball was great to both sides. And then Rondon, it was nice to see Ronnie come in there against two really good hitters, and Chappy has been throwing the ball well."

With all the attention the Cubs' starting staff has earned, their bullpen has been overlooked. Sure, it's been revamped and has had its slumps, but ranking fourth in the NL in ERA and fifth in fewest walks given up is pretty good.

"When that happened with Hendricks, everybody was locked in because no one knew who’s number would be called," Edwards said. "And we were all called -- and did our jobs."

For once it wasn't Kris Bryant or Anthony Rizzo or the Cy Young candidates leading the way. Instead, it was a group of tight-knit relievers led by the longest-tenured Cub -- setting the tone with his arm and bat -- who led the team to the brink of making to the National League Championship Series for the second consecutive season. All the Cubs have to do is beat Madison Bumgarner on Monday to complete the sweep. Considering that the Cubs' pitchers led the majors with 54 hits, maybe it wasn’t silly to ask Wood if he thinks he'll get the chance to face Bumgarner at the plate.

"If they want to let me get an at-bat, I'll take one anywhere I can," Wood said with a smile.

In the locker room afterward, veteran starters John Lackey and Lester were having some fun at Wood's expense. It's not often the middle relievers end up in the limelight. Wood was about to be ushered into the interview room where usually the manager, starting pitcher and star of the game congregate to discuss the evening's events. Wood qualified on this night, so as he put on his checkered sport coat to head over, his teammates couldn't resist needling him. Lester took note of the patterns on Wood's coat.

"With his grandma's couch, he's psyched up about it right now," Lester said.

Wood shook his head with a smile on his face and walked out of the clubhouse as the hero of the night on a team full of them. And now that team is one win away from advancing.

"We're going to go up against a tough pitcher in a couple days that is known for these situations and really pulls through, so we got to be all hands on deck and be really locked in for this next game," Wood said.

As if anyone would think differently on a 105-win team.