CINCINNATI -- When the ball left Joey Votto's bat, D-backs right-hander Merrill Kelly put his head down. He wasn't even going to watch what he thought was a sure-fire homer to center field.

"I thought it was way gone," Kelly said.

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Still with his back to where the ball was headed, Kelly lifted his head towards home plate umpire Ángel Hernández, looking for a new baseball.

Then Kelly noticed the crowd wasn't cheering like he expected for a home run and Hernández was still looking out to center field as if there were a play out there.

So Kelly whirled around and finally looked towards center-right at the moment that center fielder Alek Thomas was coming back down to the ground after reaching over the wall to make the catch. Kelly's face registered complete surprise as he looked around.

"I couldn't tell if he caught it or not," Kelly said. "You guys saw my reaction. That was part of my reaction. Like, I was trying to figure out what exactly just happened. Was it a homer? Did he bring it back? When I realized he caught it, it was unbelievable."

And it may have changed the course of the game, which the D-backs won, 7-0, to snap a four-game losing skid.

"If he doesn't catch that ball, that game could turn out a lot differently than it did," Kelly said.

Instead of the Reds being up 2-0, the catch ended the first inning and Kelly was able to get his feet back under him and settle in to throw six quality innings.

This might be the first time that Thomas, who is ranked as the D-backs' No. 2 prospect and made his big league debut last month, has robbed a home run as a Major Leaguer, but it's not the first time he's done so in a Major League park.

Growing up in Chicago the son of former longtime White Sox strength and conditioning coach, Allen Thomas, Alek would spend time as a young teen shagging fly balls at Guaranteed Rate Field. One of his favorite things to do was rob home run balls.

"[I was] probably like 12," Thomas said of the first time he robbed a homer during batting practice. "Yeah, when I was about 5-foot-6. Paul Konerko used to hit them at the wall all the time, just all those dudes. I remember it like it was yesterday. It’s pretty cool."

Thomas was out of the starting lineup Tuesday and he spent batting practice patrolling the outfield looking for home run balls to rob, grabbing a couple.

Thomas drew a walk in the fourth inning on Wednesday which put him face-to-face with the Reds’ first baseman, and Votto good-naturedly gave Thomas a hard time about the robbed home run.

"It was a pretty funny conversation," Thomas said. "At the tail end of it, he was asking me where I’m from and when I got drafted and if this is my first year or whatever. It was a good conversation. It was all laughs.”

After taking a homer away from Votto, Thomas robbed the veteran of at least a single, if not a double, when he made a diving catch on his line drive in the fourth.

Once again, not long after that, Thomas found himself on first base after singling and had to face Votto.

"I said, 'I’m sorry,' and he was like, ‘Dude don’t worry about it, man,’" Thomas said. "It was pretty funny."

Finally in the seventh, Votto got a measure of revenge when he hit a double into the gap in right-center, which led to another exchange at first base between the two later in the game.

"Then he got that hit and then I got at first again and I was like, ‘Hey, you hit it where I wasn’t,’" Thomas said. "And he was like, ‘Yeah, that’s right.’"

Despite having grown up around Major Leaguers and establishing himself as a top prospect, Thomas still was excited about his interactions with Votto, someone he grew up admiring.

“I remember looking up his stats in high school because I knew he was such a good hitter,” Thomas said. “Just to be out there on the same field with him is pretty cool. [Him] joking around with me and everything, robbing his homers and everything. It was pretty cool.”