Delivering the game-tying triple into the gap for his first career RBI, then scoring the game-winning run moments later on a balk, Eaton led the D-backs to a 6-2 victory over the Padres for the team's third consecutive win to get back to .500 on the season.
With the victory, Arizona remained 4 1/2 games back of the Cardinals for the second National League Wild Card spot with 14 games remaining.
"Triples are always fun, I love to run," Eaton said of his three-base hit off Padres starter Edinson Volquez. "It's a good time. It's important to get those runs, too."
In 12 Major League starts, Eaton has reached base 23 times for a .411 on-base percentage. On the season, D-backs leadoff hitters have a combined .324 OBP.
Once on third, after turning a typical double to left into a triple, Eaton wasn't done trying to push the issue. He thought about taking off again, but instead forced Volquez into a miscue that let him walk, not run, home.
"To be honest, I was creeping down the line and I had my mind set on, if he stepped back and goes into his delivery, I might give it a go and try to steal home," Eaton said. "So I tried creeping down the line and I think he kind of saw me out of the corner of his eye. He wasn't flustered, but I think he kind of lost his train of thought and he stepped off with his wrong foot."
The rookie's triple in the fifth highlighted a three-run inning, which also saw Justin Upton and Paul Goldschmidt deliver key doubles.
With two extra-base hits Wednesday, Upton has five in his last four games after totaling five in his previous 25. Goldschmidt's double gave him 40 for the season, making him the fifth player in franchise history to accomplish the feat.
"It's nice to have everyone contribute," Eaton said. "Couldn't ask for anything more tonight."
In earning his third straight win, D-backs starter Trevor Cahill tossed six quality innings, with both of the runs he allowed the result of free passes.
"He's had trouble with walks, but other than that he was dominant," D-backs manager Kirk Gibson said. "The rest of the game was clean for him. He pitched good."
Since the Padres defeated him on Aug. 26, the right-hander hasn't allowed more than three runs and five hits in a start, lowering his ERA to 3.89.
"I feel like I've been throwing the ball better," Cahill said. "I was a little wild but I felt like I could throw any of my pitches when I wanted to. They had been playing really good baseball and they match up well against us. They don't give in and they play us tough."
Wednesday's outing helped Cahill become the second pitcher since 1990 to record 10 wins and 30 starts in his first four Major League seasons, along with the Yankees' CC Sabathia.
"It's tough, because there are so many things that can go wrong. Hopefully my body holds up," Cahill said. "I don't always feel great, but you learn from that. You battle through it. I've been fortunate with health stuff."
After holding the Padres scoreless through the first three innings on Wednesday, Cahill finally ran into trouble in the fourth, when Will Venable and John Baker broke a scoreless tie with back-to-back RBI singles to right field.
"He's tough," Venable said of Cahill. "The ball doesn't come straight out his hand. You've got to be patient and get a good one to hit."
The D-backs answered in their half of the inning with consecutive doubles by Upton and Miguel Montero to start the frame, but the next three batters came up empty, leaving the Padres ahead, 2-1.
After Cahill settled down and provided a shutdown inning in the fifth, his offense rewarded him with three runs to give the D-backs their first lead of the game, 4-2.
"Just throw strikes, get ahead in the count and today he was able to do that," Montero said. "He made quality pitches and didn't give up very many hard hit balls. Especially with two strikes, he made good pitches."
Ryan Wheeler delivered two insurance runs in the bottom of the eighth when he hit an RBI triple to right, then scored on an overthrow into the D-backs dugout.
Brad Ziegler, David Hernandez and Matt Lindstrom pitched the final three innings to secure the win.