Ryan Waldschmidt dug in against Edwin Díaz with Arizona trailing 3-2 in the ninth inning and delivered a two-run walk-off home run that finished the Dodgers 4-3 at Chase Field on Aug. 7. The rookie hit the ball and immediately sprinted out of the batter's box, not yet sure whether it had cleared the fence.

"I started sprinting, and if it didn't get out, I was going to try and get to third, because there was only one out and it makes it a lot easier on the next guy to walk it off," Waldschmidt said. "So I started sprinting, and then I heard everyone kind of go crazy, and I looked up, and both the outfielders were just looking into the stands. So I was like, 'That's pretty sweet.'"

Arizona hitting coach Joe Mather was the first to react in the dugout, leaping onto the bench and vaulting over the railing before manager Torey Lovullo had even confirmed the ball was gone. Lovullo said it was dark enough in the outfield that the flight of the ball briefly fooled him.

"I lost it just for a second because it gets a little dark out there, and there's a lot of light colors with the baseball," Lovullo said. "But I saw the person reaching for the ball in the stands, and I was like the third guy that saw it because Joe Mather was already climbing out of the dugout. It was a very, very, very surreal moment."

Starting pitcher Merrill Kelly was not on the field to see it. Kelly had carried a no-hitter into the sixth inning before surrendering a couple of hits and exiting with a left hamstring cramp. He watched the finish from his locker on two televisions simultaneously—one showing a live overhead feed, the other carrying the broadcast on a slight delay. He heard the crowd noise first, saw Waldschmidt jogging on the live angle without knowing the outcome, then turned to the delayed feed and watched the ball land in the seats.

"I got to watch different pieces of it," Kelly said. "So that was pretty cool."

Kelly framed the win in terms of the bigger picture. "We're hitting our stride at the right part of the season, and I think, obviously, any time that you can win games later in the season against not only good competition, but the competition that you're going to be hopefully competing against when the lights turn on and when stuff really gets serious, I think it's good for the guys in here."

The win was Arizona's fifth straight over Los Angeles and extended the Diamondbacks' record in their last 25 games to 17-8. That stretch traces back to a three-game sweep of the Dodgers in Los Angeles just before the All-Star Break—a run that has reshaped Arizona's postseason position.

At 62-55, the Diamondbacks are tied with the Philadelphia Phillies for the second NL Wild Card spot. They sit six games behind the Chicago Cubs for the top Wild Card position and hold a two-game edge over the San Diego Padres, who are on the outside of the bracket looking in. The Dodgers have dropped seven straight games, their longest losing streak of the season.

This is not a team sneaking into relevance. Arizona has beaten the Dodgers five consecutive times and won 17 of its last 25 games with the postseason approaching. The Diamondbacks beat the team they will likely face again in October, did it at home in front of a near-capacity crowd, and did it with a rookie ending the game against one of the better closers in the National League.

Waldschmidt's moment defines a roster's belief in itself. He batted ninth, was the last man due up, and drove in the winning run against a closer entering the inning with a lead. The fact that he sprinted immediately out of the box—trying to stretch a single into a triple if needed—says something about how this team approaches close games. Lovullo's dugout reacted before the ball even landed. That is a team that expects to win.

Arizona plays inside a Wild Card race with Philadelphia directly alongside them and San Diego two games back. The Cubs, sitting atop the NL Wild Card picture, are six games ahead. Every game between now and the end of the regular season matters at this margin, and the Diamondbacks have already demonstrated they can take down the Dodgers on a streak.