Was the fourth inning too early for a curtain call? Veteran utility player Chad Tracy didn't think so.
"Chad told me, 'Get up there,'" Harper said. "He said, 'Who cares, you know? Get up there.'"
Harper climbed to the top step of the dugout and acknowledged the crowd with a wave of his helmet. His two home runs proved to be the difference in the Nationals' 2-0 win.
The reigning National League Rookie of the Year Award winner sent a 1-0 curveball from starting pitcher Ricky Nolasco over the wall in right-center field in the first inning. Then, in the fourth, Harper hit a 3-2 slider to the same section of seats.
The announced crowd of 45,274 -- and the Nationals' dugout -- was elated and stunned at the same time.
"You just shake your head," Nationals center fielder Denard Span said. "You just shake your head in amazement."
Harper flew out to left field in his third at-bat and fouled out down the first-base line in his fourth. But the damage already was done.
Harper joined Raul Mondesi and Carlton Fisk as the only defending Rookie of the Year Award winners to hit two home runs in the first game of the following season.
"He's just got a great stroke, got a great approach and he's a smart hitter," Nationals manager Davey Johnson said. "I'm sure he looked at the film and had a pretty good idea of how [Nolasco] likes to set up his fastball and how he likes to pitch. ... He's not just a good talent, he pays attention."
Added hitting coach Rick Eckstein: "He's always taking in information. Every at-bat that he comes back, he's always taking in information and he thinks about it, he processes it."
Harper continued to build on a torrid Spring Training in which he hit .478 and had three home runs and six extra-base hits. He was held out of a few games late in Grapefruit League play after he twice jammed his left thumb, but that injury didn't seem to affect him on Monday.
With his first shot, Harper became the fourth-youngest player to homer in his team's first game of the season, behind Robin Yount (19), Tony Conigliaro (20) and Ken Griffey Jr. (20).
After the game, Harper said that he wasn't looking to homer in his first two at-bats but simply "have good ABs and square things up."
"I just tried to react to something I could hit," he said. "Nolasco's a great pitcher; he carved us up all year last year, and he carved me up last year. So being able to get two knocks off of him, it was good for me, and I think we saw him pretty good today."