After a third quarter filled with turnovers and misses, the Boston Celtics' season looked to be on its last legs in Game 6. However, Celtics star Jayson Tatum came alive down the stretch to defeat the Philadelphia 76ers, 95-86.

By no means was it a pretty win, yet the C's live to fight another day. The series is now tied up at three games apiece before the deciding Game 7 tips off on Sunday in Boston.

At many points in Game 6, the Celtics looked ready for vacation. So how did they stave off elimination and freeze a hungry Sixers squad? Let's discuss three major takeaways from Boston's gutsy victory over Philadelphia.

3. The resiliency of Jayson Tatum

Through three quarters, Tatum was arguably having the worst game of his career. He went 0-for-10 from the field in the first half and finished with just one point. In the third quarter, he wasn't much better as he only scored one basket to bring his total up to three points.

Yet, the four-time All-Star never gave up. He showed his determination in the final quarter of Game 6, putting up 16 points while shooting 50% from the field:

He hit four triples in the fourth quarter as well, which were all huge shots that the Celtics needed desperately at that stage in the contest:

In addition, Tatum's 16 points down the stretch were more than the Sixers had all quarter. Philly's offense dragged late in the game and put up just 13 points in the final frame.

Without Tatum's determination, the Celtics would be headed back home for good. Instead, the Celtics are on their way home for a Game 7 and another chance to extend their season.

2. Joe Mazzulla's lineup changes worked well

The Celtics have started guard Derrick White for most of the season. While that worked in their favor, his lack of size wasn't working in Game 5.

In Game 6, first-year coach Joe Mazzulla made the call to start center Robert Williams III instead. Although it was somewhat of a gamble given his limited minutes in the series, it paid off well.

Time Lord notched 10 points, nine rebounds, and two blocks in 28 minutes, in which he was a plus-18. Plus, he did a good job of avoiding foul trouble and staying on the floor.

His defense on Sixers MVP Joel Embiid was huge, as Philly's big man didn't have as easy a time in Game 6 as he did in Game 5:

Even though Williams isn't a shooting threat, his role in the starting five is crucial. He tightens up the paint and has the athleticism to finish off lobs on the other end of the floor. No other Celtic can really do what he does:

After his success in Game 6, it wouldn't be a shock if Mazzulla opted for the same lineup with Williams for Game 7.

1. Marcus Smart with his best game of the season

Boston's dominant duo of Tatum and Jaylen Brown wasn't on fire in Game 6, so someone else needed to step up. Former Defensive Player of the Year Marcus Smart answered the call, as his performance propelled them to victory.

The longest-tenured Celtic scored a team-high 22 points to go along with seven assists, seven boards, and two steals. He did it all for the C's and also came through in the clutch with big buckets when Boston needed it:

When Tatum and Brown looked rattled by Philly's defense early on, Smart was there to relieve the pressure. He has struggled at times in this series and even missed a game-winning opportunity in Game 4, yet he was there when the Green Team needed him most on Thursday night.

Prior to Game 6, Smart told the media that he was prepared to do anything to go out and get a win. He backed up his talk over the course of the gritty victory and will have to do it again on Sunday night for Game 7.