One big swing of the borrowed lumber later, Harper was on the top step of the dugout, roaring back at the fans chanting "MVP! MVP!" for their $330 million man.
Harper homered deep into the second deck in right-center field for his first hit with Philadelphia and celebrated with an emphatic curtain call, highlighting the Phillies' 8-6 win over the Atlanta Braves on Saturday.
Harper, swinging Williams' stick after a slow start to the season, crushed Jesse Biddle's fastball 465 feet with two outs in the seventh. Fans gave Harper a standing ovation, hollering and clapping in a fashion rare for March baseball.
After getting high fives in the dugout, Harper climbed out for a curtain call, throwing both fists in the air and shouting "Let's go!"
"It was a really cool moment," Harper said. "The fan base, the stadium, the electricity we have in this place, it all came together."
"Offense definitely created some electricity in the ballpark, and I think that's going to be our defining characteristic," Phillies manager Gabe Kapler said.
Harper -- wearing bright blue cleats instead of the gaudy, green Phanatic spikes he sported on opening day -- unfurled the powerful left-handed swing that has Citizens Bank Park rocking like it was 2008, the last time the franchise won the World Series.
Prior to his homer, a hitless Harper was just like the rest of the red-clad fans -- cheerleading the other Phillies hitters.
Harper greeted Franco after his homer with an elaborate celebration outside of the dugout, the two of them mock shooting a bow-and-arrow. They did the same jocular celebration when Harper went deep.
Harper already has unique celebrations with many of his teammates. He simulated a basketball layup with outfielders Andrew McCutchen and Odubel Herrera after both wins. On Thursday, Harper was the basket. On Saturday, he mock dunked into the arms of Herrera.
"We have a great group of guys, a lot of energy," Harper said. "(The celebrating) just adds to the fun."
Besides power at the plate -- not to mention the box office and merchandise shop -- Harper has brought much-needed energy to the Phillies, who are hoping to end a seven-year postseason drought.
The club's start hasn't disappointed in the least.
Adam Morgan (1-0) faced one batter in the fifth inning.
The game was tied at 4 in the fifth when Realmuto lined a two-run homer to left-center off Wes Parsons (0-1).
Franco hit a two-run shot off the foul pole in the fourth. He's the sixth player in franchise history to homer in each of the team's first two games, joining Hall of Famers Mike Schmidt and Chuck Klein, plus Howard, Scott Rolen and Danny Litwhiler.
Phillies starter Nick Pivetta allowed four runs and eight hits in 4 2/3 innings.
Atlanta's Bryse Wilson, a 20-year-old rookie making his second career start, gave up four runs and five hits in 3 1/3 innings.
"We're just having a hard time keeping them in the ballpark," Braves manager Brian Snitker said. "It's a very explosive offense. ... We're just going to have to keep fighting, come out and get one tomorrow."
Harper's home run ball was collected by two Braves fans from Tennessee, he said. The slugger, who received the ball postgame in a yellow envelope from a Phillies official, will send the fans a bat and ball as thanks.
The Phillie Phanatic returned the favor after Harper honored the fuzzy, green mascot on opening day. The Phanatic's oversized sneakers featured images of Harper's face on the toe.
Atlanta: Ender Inciarte fouled a ball hard off his right foot in the seventh inning but was OK.
Philadelphia: Right-handed reliever Tommy Hunter (right flexor strain) felt soreness while rehabbing in Florida on Thursday. His anticipated mid-April return likely will be pushed back as a result.
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