Neither could his teammates from Tokyo after Osaka's third home run of the game put an exclamation point on Japan's 12-2 victory over Tennessee in five innings in the Little League World Series title game Sunday.
The 12-year-old Osaka added a triple for good measure, too, to top off his 4-for-4 afternoon. In a symbolic gesture, Japan's players jogged the traditional postgame victory lap carrying the flags for both their home country and the United States.
"We had such a great time in Pennsylvania and we really played a good game today. It was kind of a, 'Thanks,'" Osaka said through an interpreter.
Starter Kotaro Kiyomiya struck out eight in four innings and added an RBI single for Japan. The game ended in the fifth after Osaka's third homer made it a 10-run game.
"We thought we played the best in the tournament so far, especially to win by the 10-run rule in the finals," said 12-year-old Rintaro Hirano, who homered in the fourth to make it 10-1.
A day after pounding out a 24-16 win over California in the U.S. title game, the Goodlettsville, Tenn., sluggers could only muster two hits - solo shots by Brock Myers and Lorenzo Butler.
It was a bittersweet final game for two teams that grew close during their two weeks in South Williamsport. They exchanged customary postgame handshakes at the plate before Japan received the World Series championship banner and took their warning-track run.
"Tennessee was our best friends in the U.S. division," Kiyomiya said.
Japan's jog finally stopped in front of the team's giddy cheering section as proud family members and friends stood shoulder-to-shoulder to take pictures through the infield fence.
There were so many highlights, including five home runs off Tennessee pitching.
That was more than enough offense for 13-year-old ace Kiyomiya, who had a fastball clocked in the high-70s, The right-hander with the hitch in mid-delivery pitched like a big-league ace in allowing just one hit.
Regardless, this is still a banner year for Goodlettsville after its exhausting victory Saturday over Petaluma, Calif., for the U.S. championship. That game set a record for most combined runs in the World Series.
The thrilling victory kept the Tennessee players and their families up late into the night.
"(The parents) must have partied harder than the kids did," manager Joey Hale said. "I knew we'd be flat today."
Tennessee lost a 10-run lead in the bottom of the sixth of that game before scoring nine times the next inning to finally put away Petaluma in a Little League classic. Even more impressively, Butler had three homers and a record nine RBIs - a feat so unique the 12-year-old's name became a trending topic on Twitter.
Butler went deep again off reliever Osaka in the fifth - Butler's fourth homer in two days - to cut the lead to 10-2 and give Goodlettsvile some home hope. Tennessee's mini-mashers have proven they can break out any time at the plate.
"It feels really good and it was really great," Butler said simply about his hitting exploits. He said his three homers Saturday were the longest he had hit all season.
Its pitching depth sapped, Tennessee turned to right-hander Justin Smith to start against Japan - the first time the 12-year-old had pitched in the World Series or in Southeast regional tournament.
"Everybody knew our pitching was depleted and we were bound for a letdown," Hale said. "I'm not saying we were going to beat Japan. I think they were the best team here at everything by far, pitching, hitting. But I think last night is how we want to be remembered."
Leadoff hitter Osaka, 12, didn't waste any time with a first-pitch triple to the right-field corner in the first. Kiyomiya delivered his RBI single two batters later to get the scoring started.
Osaka then homered in the second to left-center, just in front of the "Little League" sign above the fence, before leading off the fourth with his second homer, this time to center, for a 6-1 lead.
The Kitasuna league all-star team from Tokyo won Japan's eighth Little League title and second in three seasons.
While his players danced around in delight after the game, skipper Yoichi Kubo teared up. He kept his composure after managing a team that won the World Series in 2001, "but I was crying this time when we won this game as world champion," he said.
Smith pitched admirably in a tough spot, allowing five runs and seven hits over three innings while striking out three. His team was trying to make history as the first squad from Tennessee to win youth baseball's biggest prize.
Goodlettsville also was the first Tennessee team to advance to South Williamsport since Morristown in 1987. The suburban Nashville crew counts among its fans Rays ace David Price, who is from Murfreesboro.
They might be done with baseball for now, but the celebration is just beginning back home. On Tennessee's social calendar is a visit to the Vanderbilt season opener Thursday night against South Carolina.
"When we get home, it's going to be a carnival," Hale said.