Jayson Tatum scored 23 of his 50 points in the third quarter to propel the Boston Celtics to a playoff berth after defeating the visiting Washington Wizards 118-100 at TD Garden in the Eastern Conference's play-in tournament.

Tatum shot 14-of-32 for the game and hit all 17 of his free throws. Kemba Walker added 29 points for the C's.

The Wizards' dynamic duo of Russell Westbrook and Bradley Beal struggled from the field, scoring their 42 points on 16-of-43 shooting. Westbrook added 14 rebounds and five assists.

The Celtics will be the East's No. 7 seed. Washington can still make the playoffs but needs a victory against the Indiana Pacers on Thursday at Capital One Arena to qualify as the Eastern Conference's No. 8 seed.

Indiana defeated Charlotte 144-117 earlier Tuesday in a play-in game to earn a date with the Wizards.

Notable Performances

Celtics F Jayson Tatum: 50 points, 8 rebounds, 4 assists

Celtics G Kemba Walker: 29 points, 7 rebounds, 2 steals

Celtics C Tristan Thompson: 12 points, 12 rebounds

Wizards G Bradley Beal: 22 points, 9 rebounds, 6 assists

Wizards G Russell Westbrook: 20 points, 14 rebounds, 3 steals

Wizards G Ish Smith: 17 points, 8 rebounds, 2 steals

Tatum's Tremendous 3rd Quarter Puts Celtics in Playoffs

Tatum nearly outscored the Wizards by himself in the third quarter, with Washington posting only three more points than the Celtics star.

He shot 7-of-10 from the field and 7-of-7 from the free-throw line in the third quarter and hit his buckets in bunches.

Of note, his aggression around the paint put the Wizards in a bind.

The 23-year-old started his third-quarter effort with a three-point play to give the C's an early second-half lead.

After Beal hit a jumper in response, Tatum dished to Walker for a three-pointer that gave Boston the edge for good.

That was the first of three Tatum assists to Walker, who went on a personal 9-0 run thanks to a trio of three-pointers. Boston added four more points to cap a 13-0 stretch.

Tatum eventually scored 10 in a 1:27 span in the first part of the quarter, giving Boston its largest lead of the game at 74-58.

He checked out for a minute-and-a-half before adding another 10 points in the final 3:10.

Tatum ultimately either scored or assisted on 32 of the Celtics' third-quarter points.

His effort forced Washington to play catch-up in the fourth, and the differential was too big to overcome in the end, with the Wizards unable to cut the lead within seven.

There was no shortage of compliments for Tatum's work:

He also found himself alongside a Celtics franchise legend in the record books:

Overall, it was a sensational night for Tatum, who may need a few more heroic performances for Boston to make a playoff run. Given how well Tatum performed, however, it's certainly possible seeing that happen.

Outside Tatum, Wizards' Poor Shooting, Mistakes Help Lead to Loss

The Wizards lost primarily because Tatum took this game over in the third quarter, but they had their chances to get back in it.

However, Washington had too many problems outside defending the Celtics' superstar.

For starters, it was an off night for Westbrook, who has largely been sensational this year as he resembles his 2016-17 NBA MVP-winning self. The triple-double machine had a rough game, shooting just 6-of-18 from the field and scoring just six points after halftime.

Westbrook entered Tuesday averaging 23.7 points, 13.3 rebounds and 13.3 assists in his last 36 games, and this team isn't finding itself in a win-and-in position for a playoff berth without him. He very well could end up posting a monster triple-double Thursday to put Washington in the playoffs.

But Tuesday's loss falls on more shoulders.

Davis Bertans missed all seven of his three-pointers, and the Wizards shot just 3-of-21 from three-point range as a team.

Wizards starters not named Beal or Westbrook scored just 13 points combined.

Washington also committed some costly mistakes, with Boston scoring 20 points off turnovers compared to the Wizards' six.

Washington also had no answer for Walker, who drilled six three-pointers.

Ultimately, the Wizards still survive for at least one more day, so this loss could be moot. In the end, Tatum was too strong, and Washington didn't play well enough to keep pace with the C's.

What's Next?

The Celtics will face the No. 2 Brooklyn Nets in the first round of the playoffs. That series will begin Saturday at a to-be-determined time.

Washington will host the Pacers on Thursday at 8 p.m. ET, with the winner advancing to play the No. 1 Philadelphia 76ers in the first round beginning Sunday.