It all came down to a single swing, but in the end, Cubs slugger Kyle Schwarber fell just short of winning the Home Run Derby. 

With an exceptional display of power and clutch hitting, Nationals star Bryce Harper rallied in the final round, connecting on pitches from his father to beat Schwarber 19-18.

Harper hit the contest-winning blast in extra time, the reward for hitting two homers at least 440 feet during the 4 minutes of regulation. After he connected with the game winner, the Nationals star immediately went into celebration mode.

"We have some of the best fans in all of baseball, and to be able to that with my family out there, that's an incredible moment, not only for me but for the organization and the Nationals fans," Harper said.

Wearing a headband that resembled the District of Columbia flag and displaying a right sleeve with stars and stripes, Harper trailed 18-9 with 1:20 left before rallying. He homered on nine of his last 10 swings before entering extra time.

Harper, who has 23 home runs this season, advanced to the final with an astonishing spree of longball hitting. He trailed Max Muncy of the Dodgers 12-4 with 2:20 left, then peeled off six homers in 47 seconds before calling a timeout.

Harper returned to hit three more home runs in 22 seconds, the last of them inside the right-field foul pole.

The semifinal matchup between Schwarber and Philadelphia's Rhys Hoskins went down to the final swing. After stunning top-seed Jesus Aguilar of Milwaukee in the opening round, the eighth-seeded Hoskins ripped 20 long balls to put the pressure on Schwarber.

Using a late surge, Schwarber pulled one ball after another over the right field wall to squeeze out a 21-20 victory — by far the highest-scoring matchup of the night.

The most thrilling first-round match featured a near buzzer-beater by Houston's Alex Bregman, who fell to Schwarber 16-15. The difference was the pair of homers that Schwarber hit during 30 seconds of extra time.

Bregman — the lone AL representative — appeared defeated with a minute left, but he mounted a late surge and lost when his final swing produced a drive that landed at the base of the center-field wall.

Muncy advanced by defeating No. 6 seed Javier Baez of the Cubs, 16-15. Baez hit the longest shot of the Derby, a 479-footer.