Jayson Tatum busted out on Monday night for the Boston Celtics in their series opener against the Philadelphia 76ers. The Celtics superstar went off for 39 points and 11 rebounds, but in the end, Tatum's heroics just weren't enough. James Harden was the man of the hour as he led the Sixers to a huge Game 1 victory in Boston.

Thanks to Harden's career playoff-high 45-point eruption, the Sixers were able to steal away Game 1 at the TD Garden, thereby snatching home-court advantage from the No. 1 seed Celtics. Despite taking a significant advantage in the series, Harden and Co. have no intention of settling:

“I mean, we didn't come in the game expecting to lose,” Harden said after the game. “We are here to win. Even after this game, I told the guys, ‘Don't get too happy. We even-keeled.' We're coming here to get Game 2 as well. That's the mindset that we have as a unit. Whether [Embiid] comes back or not, we're ready to go.”

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Harden did concede that Embiid is “everything for this team,” but at the same time, James also knows that the Sixers will need to make do with “whoever's on the floor.” Thankfully for Philly, they had Harden on the floor on Monday night. He carried the Sixers to an unexpected win, which left Tatum and the Celtics shell-shocked.

These two teams do it all over again on Wednesday, and you can be sure that Boston will be out for some revenge. They simply cannot afford to lose Game 2.