LONDON -- At various times since their jet touched down, members of the Yankees' traveling party have referred to the London Series as having the characteristics of a business trip, a spectacle and high-stakes playoff games. Once the first pitch was thrown on Saturday, we saw what the Red Sox and Yankees always seem to provide: unforgettable theatre.

Aaron Hicks slugged the first Major League home run on European soil to cap a six-run first inning for the Yankees, and there was tons of offense to follow. Brett Gardner and Aaron Judge also cleared the fences, while DJ LeMahieu collected four hits and drove in five runs in an unforgettable 17-13 slugfest victory over the Red Sox at London Stadium.

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"It was two good teams going at it," Judge said. "We've got a good ballclub here with guys stacked one through nine, just like they do. They're the defending champs, and with the top of their potent lineup, this is something that can happen. I'm just glad we came out on the winning side of that."

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Neither starter completed the first inning, as the Yankees tagged Rick Porcello for six runs and five hits, with Porcello recording only one out.

Luke Voit drilled a run-scoring double, one of his four hits before leaving the game with a lower abdominal injury, Netherlands-born Didi Gregorius pounded a two-run double and Edwin Encarnacion doubled home another run before Hicks slugged a projected 386-foot blast, per Statcast, into the Boston bullpen in right field.

"We just kept on scoring," Gregorius said. "Everybody got on, did their job, and then it just went on that way. We came out on top in the end, so that's all that matters."

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The Red Sox responded against Masahiro Tanaka, who permitted six runs on four hits and was chased by Michael Chavis' three-run homer over the batter’s eye in center field. Though the 385-foot marker was a focal point in Friday's workout, Chavis' drive cleared the 16-foot wall easily.

Rafael Devers, Christian Vázquez and Brock Holt also drove in runs off Tanaka, who walked two and recorded two outs in his 37-pitch appearance.

"Obviously it was a struggle for both sides in the pitching department," Yankees manager Aaron Boone said. "Those are things I guess we’ll evaluate a little bit better when you’re removed from it. It just felt like a lot of good hitters took advantage of mistakes."

A frenzied crowd of 59,659 fans drank it all in on a steamy 92-degree day, munching hot dogs and popcorn as they watched the action on the same grounds where the 2012 Summer Olympics were held. They cheered passionately for both teams, prompting some to remark that it was one of the best environments they could recall.

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“I think the introductions were pretty cool, seeing both national anthems and then the fireworks at the end," LeMahieu said. "I kept looking up throughout the game and seeing how many people were there. It was just one of those once-in-a-lifetime experiences."

"The atmosphere was crazy," Gregorius said. "It's what you want to see. It was like a soccer match, but with baseball. The fans were into it since the game started. It was pretty cool."

New York reclaimed the lead in the third inning on Gardner’s two-run homer off Steven Wright, then pulled away with a six-run fourth that was highlighted by LeMahieu’s three-run double and Judge’s 375-foot, two-run homer to right field.

Chad Green and David Hale combined for three scoreless innings to quiet the Boston bats, and New York scored another three runs in the fifth, two driven in by LeMahieu. On the Yanks' bench, someone asked LeMahieu if this felt like a return to Denver's mile-high altitude.

"I think tonight was kind of beyond a Coors Field game," LeMahieu said. "It was like something I’ve never played in or been a part of."

That exhausted the Yanks' output, but Boston had one last gasp, peppering Nestor Cortes Jr. and Tommy Kahnle for six runs in the seventh -- including Chavis' second three-run homer of the game. Adam Ottavino, Zack Britton and Aroldis Chapman finally slammed the door, protecting the hard-fought victory.

"It felt kind of like an exhibition, a spectacle," Ottavino said. "Obviously we knew we had to win, but it was just one of those games -- six runs right out of the chute, and then they get six. Then we were up by like 10 or more at one point. Everyone kind of relaxes again and then it came back the other way. There was a lot of stuff going on between innings. It just felt like a strange environment."

At four hours and 42 minutes, it missed becoming the longest nine-inning game in Major League history by three minutes -- that Aug. 18, 2006, contest, it should come as no surprise, was also played between the Red Sox and Yankees. Boone said he looked deep into the crowd at times and pondered how a first-time observer might have been absorbing the affair.

"I was wondering [if they were thinking], ‘Man, this is pretty long,'" Boone said. "Then I thought, ‘Well, cricket takes long, all weekend to play, so I’m sure a lot of people are used to it.’ They saw a lot of great hitters do some great things. There were some really good defensive plays as well. But we should remind them that there are not 30 runs every game.”