CINCINNATI -- From the moment he walked into Great American Ball Park on Friday, Reds infield prospect Spencer Steer wanted to soak in everything about his Major League debut. The night ended with Steer getting downright soaked with a water cooler by teammates.

Debuts don't get much better than this. Steer reached base in all four plate appearances, mashed a home run for his first big league hit and scored the winning run in the bottom of the ninth in Cincinnati's 3-2 walk-off win over the Rockies.

"You don’t know what to expect coming up to the big leagues, it’s a lifelong dream," Steer said. "You can’t really know what to expect until you do it. Today, I made memories that will last me the rest of my life."

The rookie finished the night 2-for-2 with two walks. The last Reds player to reach four times in his Major League debut was Jay Bruce in 2008. Steer is only the 11th player ever to reach four times with a homer in his debut, and he’s the first Cincinnati player to do it.

Steer, the organization’s No. 7 prospect, was acquired on Aug. 2 in the trade that sent starting pitcher Tyler Mahle to the Twins. One of 10 prospects the Reds acquired in a series of trades this summer, he is the first to reach the big leagues and offer a glimmer of hope during the start of a rebuilding process.

In his first plate appearance against Colorado lefty Kyle Freeland, Steer went from a 1-2 count to working a 10-pitch walk in the second inning.

"What an incredible debut. He put together incredible plate appearances," Freeland said.

Leading off the bottom of the fifth, Steer crushed a 2-1 Freeland pitch to center field for his first big league hit and home run as fans at Great American Ball Park roared with approval.

"To be honest, I felt nothing. Looking back, I knew I hit it well," Steer said. "It’s a moment where you black out. That’s something you dream of. For it to actually happen, I can’t really remember much."

Injured Reds first baseman Joey Votto, who also hit a home run for his first MLB hit, was in the television booth doing some play-by-play when Steer hit his homer.

"I hadn’t met [Votto before Friday]," Steer said. "They had a 15-year in the big leagues celebration and got him a really cool gift. I was able to say hi. He congratulated me on getting called up."

As Steer touched home plate, he pointed towards the seats where his family from Southern California was jumping up and down with excitement.

"I could hear them," Steer said. "They were extra loud tonight, which was awesome. You had to show them some love because you do it for them. It was special. Everyone that supported me through my entire life was here tonight. I had to show them some love."

Steer led off the ninth with a double toward the right-field corner and took third base on a wild pitch. With runners on second and third base and Colorado using five infielders with one out, Jonathan India hit a chopper to the middle of the infield.

There was no throw to the plate as Steer scored. It was India's first walk-off hit.

"Amazing debut," India said of Steer's night. "That's really hard to do. I'm happy for him. He's a good kid and he's going to have a good career. I'm excited for him."

As Steer did a TV interview on the field after the game, teammates TJ Friedl and Graham Ashcraft doused him with the contents of a water cooler.

"Even for the most polished, it’s still a lot going on your first day," Reds manager David Bell said. "Not only coming to the big leagues for the first time, but the first time in the organization knowing pretty much nobody here or very few people. It can have a tendency to really move fast on you.

"Then the game starts, and before you know it, it’s over. I happened to walk into the ballpark from the parking lot with him and just right from the beginning, everything was calm and under control. He was taking it all in. I think that polished approach carried over to where it was slow enough to where you could really see the kind of player he is."