CHICAGO -- The story went like this: Chicago Cubs reliever Pedro Strop was headed back to the bullpen after using the bathroom in between the top and bottom of the eighth inning. He saw infielder Javier Baez getting ready to hit and decided to "pump him up."

"I went to Javier and told him, 'You have to take charge of this game right now,' " a smiling Strop said after the Cubs' 1-0 win Friday night in Game 1 of their National League Division Series with the San Francisco Giants. " 'I feel like you are the power guy in that inning.' I was screaming, 'You better do it. Hit that s--- far away. Just swing it.' "

The Cubs and Giants were locked in a scoreless battle with starters Jon Lester and Johnny Cueto not giving an inch to the other side. Wrigley Field was tense. One moment could change everything.

So how did Baez respond to Strop?

"He said, 'All right, I'll do it.' "

Javier Baez celebrates following some good advice and taking charge with his decisive eighth-inning home run. Jonathan Daniel/Getty Images

And do it he did. Baez took a 3-2 pitch from Cueto and hit it high into the air. No one knew for sure if it would come down in left fielder Angel Pagan's glove or land in the stands. Reliever Justin Grimm said it felt as if the ball "was in the air forever." Eventually it landed, just out of the reach of Pagan and into the home-run basket, sending Wrigley Field -- and the Cubs' bullpen nearby -- into a frenzy.

"When he first hit it, I thought it was out then I noticed the wind was holding it up so I sat back down," Grimm said. "Then I went nuts."

He's not the only one as Baez earned a curtain call, and a few minutes later the Cubs had their 1-0 series lead. The irony is Strop might have talked Baez out of trying for something much smaller than a home run -- or perhaps it was just the Giants' defense.

"I was thinking about bunting and the third baseman was playing in," Baez said. "So I knew Cueto was pitching me inside all day, I mean all night, just waiting for him to make a mistake and he finally did."

Cueto tried to quick-pitch Baez on the full count, but the Cubs' second-year player was ready for it. Not that long ago, Baez would have picked up his front leg and tried to destroy the ball, as he did almost every time at the plate back then. Those days are long gone -- Baez kept his foot down and simply used his quick bat to send the ball high into the sky. It was a big swing, but it was controlled. It was a swing his manager thoroughly enjoyed.

"I don't think it's any coincidence that he ended up hitting a home run because of what he had done in his earlier at-bats," Joe Maddon said. "He was up there working good at-bats. He wasn't trying to do too much. Even the home run, I mean, it wasn't his 'A' hack, but it was in an area that he can do that with, so he didn't try to force something."

The transformation of Baez has been years in the making. He came up through the minors as a brash, semi-cocky first-round pick in 2011. A leftover, if you will, from the previous regime. He wasn't part of Theo Epstein's grand plan -- until he forced his way into it.

"That guy has a flair for the dramatic," teammate Kris Bryant said.

Bryant is the opposite of Baez. In his first spring training, Bryant kept to himself, preferring to be seen rather than heard. That wasn't Baez, who recalled a time when he spoke up in his first spring with the big-league club and paid the price.

"They sent [former Cub] Alfonso Soriano to the back fields and I stayed on the main field so I told him, 'Go back there with the rookies and hit,' " Baez recalled late Friday after the celebration died down. "I told him, 'This field is for the starters.' After that workout, my car was dressed up. I was like, 'Oh, man.' "

Back in 2013, Javier Baez earned getting 'Rookie on Board' treatment from his teammates after ragging veteran Alfonso Soriano. Jesse Rogers/ESPN

Baez came out to the parking lot to find his car decorated and with a sign on the bumper reading "Rookie on Board." Back then, he was known for his brashness and, of course, his big swing. Times certainly have changed.

"You never heard anything about his defense," Bryant said. "It was just homers. Now he's a Gold Glover at three different positions. He realized that he doesn't have to swing as hard as he can every time to hit a home run. We saw that today.

"I've seen a night-and-day transformation. Now he does it all."

To top off his night, Baez, playing second base, made the final play of the game, ranging toward second and throwing on the run. As usual, he made the tough play look easy. Then there was the pickoff at first base earlier in the game as he was covering the bag during bunt defense. And his tag plays are starting to fill up the iPads of opposing scouts.

"He's growing mentally," his lockermate Strop said. "He's a totally different hitter. He's a totally different player. Last year we all saw he was just a swinger. Now it looks like he knows the situation and he knows the game."

Who does Baez credit the most with bringing out the best in him? Who else but retiring catcher David Ross, the other star of the night (albeit on defense).

"Every mistake that I make or almost a mistake, he comes to me and we talk about it," Baez said. "I've been having great relationships with the older guys. I show the respect that I need to show them so I can get it back."

Remember the Soriano story from the spring of 2013, then consider that last statement. That's a young player who has come a long way. And now he has won a postseason game, drawing the Cubs to within 10 wins of the unthinkable. People will ask if the "super utility" player -- as Bryant called him -- will be in the lineup Saturday. How can he not be? Baez does it all.

"He's kind of the X factor," Bryant said. "Looking at his progression when he first got called up from last year to this year, it's like night and day. Joe preaches 'be yourself' and he certainly was himself today."