The moment came in the fifth inning. It had no bearing on the outcome, an 8-4 Washington victory. It did not lead to a run. But it was instructive about what kind of a player Harper is.
With two outs and none on, Washington leading by two, Harper singled sharply to right. The ball was hit directly at Braves right fielder Jason Heyward, and it was hit well enough so that it would reach Heyward in little time.
Heyward came in on the ball just a bit casually, but this had routine single written all over it. Except, to Bryce Harper; to him, it said second base.
Harper never hesitated coming around first. Heyward bobbled the ball ever so slightly. But Harper was headed for second at top speed before that happened. What looked a lot like "He's trying for second? You've got to be kidding me," suddenly turned into Harper sliding into second, comfortably ahead of the tag.
The play was scored a single and an error. That was a standard scoring decision. But you wished there was a way to get Bryce Harper something more than a single there, some additional credit for hustle, for awareness, for baseball intelligence; all of it blended of course, with a large amount of speed.
"You know, that's a heads-up play," Nationals manager Davey Johnson said. "Heyward went after it kind of nonchalantly.
"After the play [Heyward] went like this," Johnson said, tapping his chest. "'My fault.' He knew it. I used to get a lot of extra-base hits where you hit the ball and if the guy didn't come in hard, just keep running."
It was a hot day in late May at Turner Field, still 91 degrees at 6 p.m. But the one guy who wouldn't be playing at anything like a languid pace would be Bryce Harper.
"If the outfielder doesn't come hard, I usually take the next bag," Harper said. "I came hard out of the box. I was on my way [to second] before he bobbled it, and then once he bobbled it, I knew that I was pretty much surely in there."
Here is another solid indication of who Harper is and will be as a player. He liked this play better than the seventh-inning solo home run off Venters.
"Absolutely, a good hustle double, that's always fun," Harper said. "Maybe they didn't give it to me, but I thought it was. You know, I like doing that. It's part of my game."
The solo home run rounded off a productive day at the plate for Harper, who was 2-for-4 with a walk. It was Harper's third home run and his first off a left-hander. He becomes just the third left-handed batter to homer off Venters.
Harper, just 26 games into his big league career, has made steady progress at the plate, making consistently hard contact. After a difficult start, his numbers are respectable (.278, .366, .495) and obviously trending upward.
"I feel pretty good up there right now," Harper said. "I think it's just a matter of time before I get going. I struggle at the beginning usually and once I see guys and what not, that's when things really get going. Having guys around me that can really swing it helps, also. [Ryan] Zimmerman hitting behind me scares some people."
The hype has been legendary for the arrival of this player. But you watch him play and you understand; he is more substance than hype. The image that will stick from this game will be Bryce Harper getting two bases on what for the vast majority of baseball humanity was a completely routine single.
"Whatever his age is," Johnson said with a smile, "that was a pretty damned good play."