Geoff Blum was barely even on the White Sox in 2005.

The 32-year-old was dealt at the July 31 Trade Deadline to Chicago from San Diego. The Padres moved him because they already had a third baseman in Joe Randa. The White Sox saw him as a backup infielder or outfielder who could "give manager Ozzie Guillen additional options when filling out a lineup."

Blum hit .200 with one home run in 31 games for the White Sox down the stretch. He had just 95 at-bats. Still, come October, he was added to the postseason roster for his versatility and ability to switch-hit. But even then, up through Game 2 of the World Series, Blum had just one appearance: He pinch-hit during the White Sox ALDS Game 1 blowout against the Red Sox and popped up to second base.

And even up until the 14th inning of World Series Game 3, when Blum made his second and final appearance that postseason during a 5-5 tie with the Astros, he wasn't really supposed to hit.

"Myself and Pablo Ozuna were the last ones left on the bench," Blum tells MLB.com. "Ozzie came down to us in the top of the 13th inning. ... The pitcher was hitting fifth or sixth that inning and he told me that I'd hit for the pitcher if he came up in the 13th. [He told] Pablo, if the pitcher doesn't come up, we're gonna double-switch [Ozuna] to second base for Tadahito Iguchi."

The pitcher's spot never came up and Blum was "dejected" knowing he wasn't going into the game. But then, Ozzie -- as Ozzie was prone to do -- had a sudden change of heart.

"Ozzie turns around to me and looks at me and says, 'Blummer, you go to second base!'" Blum recalls, laughing. "You know, just kinda spur of the moment."

So Blum was back in the game. The White Sox held the Astros scoreless in the bottom of the 13th and Blum was due up third in the top of the 14th. Nerves began to creep in and the seven-year veteran was kind of hoping someone else would get a big hit before it got to him.

"Jermaine Dye was up first. He won the MVP in that 2005 World Series, so he obviously got a base hit and got on base," Blum recalls. "And as Paul Konerko's going through his at-bat, I'm thinking, 'Man, PK has been swinging the bat well, too. I really hope he hits one out. That would take some of the pressure off me.' Then I'm thinking, 'What if he walks him and I have to lay down a bunt in the biggest at-bat of my life?' It may not have looked like it at the time on deck, but it was like a duck on the pond. On top, it's nice and calm, but underneath the wheels are spinning and it was getting out of control there for a little bit."

Konerko did none of what Blum was thinking or hoping he'd do, and hit into a double play. So now, it was up to Blum to try and get some sort of rally going with two outs. A guy who'd had just one plate appearance all month. Was Blum, a hitter who had just 62 career home runs to his name, imagining go-ahead homer?

"Oh hell no," Blum says, laughing. "My idea was just get to second base somehow. Just get to second base. As soon as the count went to 1-0, I said I'm gonna take until he gives me a strike. Lo and behold, he throws 2-0. And then I thought, there's no way I can take 2-0. This might be the best pitch I get to see in the at-bat."

After playing with the Astros in '02 and '03, Blum had learned some things and figured reliever Ezequiel Astacio would throw a fastball outside.

"I'm just gonna try to hit a line drive to left field, maybe shoot that gap in left-center and get to second base," Blum says. "But, as luck would have it, Astacio missed his spot by a good foot and a half down and in, and it just became an unconscious reaction to a pitch that was down and in. I squared it up."

6-5, White Sox.

If you watch the video, you can see Blum sprinting with his head down. He thought he maybe hit it too hard to get up and over the wall. But then, when he saw first-base coach Tim Raines leaping "nine feet in the air" and the sigh of the crowd, he knew he had hit a huge solo homer.

"The God's honest truth is I don't remember touching the bases," Blum says. "The world came back to life only when I hit home plate."

Blum also said he kept his head down most of the way because he didn't want to show emotion in front of his former teammates and friends Craig Biggio or Jeff Bagwell.

"I didn't want to disrespect them," Blum says. "That was awkward, because obviously I wanted to jump up and down and do some cartwheels."

Blum's favorite reactions from teammates were by A.J. Pierzynski -- who was happy someone hit a home run so the game could end and he could finally eat dinner -- and also the smiles from the other three backups in the dugout: Willie Harris, Ozuna and Chris Widger. The four of them had developed a kind of bond, calling themselves "Group 4." They were extras on the team and whenever one of them had a big moment, they all basked in it together.

The Sox scored one more run in the top of the 14th to make it 7-5, and then Damaso Marte and Mark Buehrle shut down the Astros in the bottom half to win the game. Chicago finished off the four-game sweep of Houston the next night behind seven scoreless innings from Freddy Garcia in a 1-0 victory.

Blum was officially a superstar. He went from utility backup barely-playing infielder to White Sox World Series hero for all eternity overnight. Fans and players raved about him. He was bombarded with text messages. And then, the next season, when Blum was back on the Padres (San Diego was where his wife and newborn triplets lived), the man who played just 33 games in White Sox black and white got the ultimate honor: A monument outside U.S. Cellular Field.

"Did I expect to have a monument with a team I played 30 games with? Hell, no," Blum says. "It was astonishing."

Blum's wife Kory first heard about the monument and wanted to surprise her husband during a Padres-Cubs game in 2006. She and the kids came to Chicago with him and she asked if she could invite his mom and her mom and do a mini-tour of the city. Blum wasn't sure why his wife wanted to do this, but he agreed. And then, when they drove up outside of U.S. Cellular Field and he saw the monument, he realized what was happening.

"You know, my mom's there and -- you start balling," Blum says, choking up over the phone. "It was great. Unbelievable. I don't know how they came up with that idea but, man, I'm grateful for it."

Weirdly, Blum played for the Astros again from 2008-10 and is now the team's TV broadcaster. He says there was definitely some bitterness and joking about it when he played with them the second time, but the real awkwardness came when he joined the booth in 2013.

"Every time I said the number 2005, my Twitter feed would blow up with reminders of how much they hate me," Blum says. "Obviously in 2017, history was made in a lot of different ways, but [the Astros] winning that championship kind of took the edge off of what happened in '05."