If the sense of urgency for the Memphis Grizzlies to snap out of their funk weren't already at critical, it sure should be now.

As a result of their five losses in six games in the bubble, the Grizzlies (33-38) have ensured a play-in game will be necessary on Saturday to determine the eighth andfinal seed for the playoffs in the Western Conference. Their first of two games left to guarantee a spot in that contest takes place Tuesday evening as they face off against the Boston Celtics near Orlando.

As part of the NBA season restart plan, the play-in game was added in the event a ninth-seeded team in a conference finishes within four games of the eighth seed, which is now guaranteed to happen in the West. The Portland Trail Blazers (33-39) are a half-game back of the Grizzlies for the eighth seed, with the Phoenix Suns (32-39) and the San Antonio Spurs (31-38) both one game off the pace.

The Grizzlies held a 3 1/2-game grip on the No. 8 spot in the West when the season paused as a result of the coronavirus pandemic. They dropped four straight upon their return and were back in the loss column Sunday with a 108-99 defeat at the hands of the Toronto Raptors.

"I'm not worried about no play-in game right now," rookie guard Ja Morant said. "Our focus now is learning from our mistakes from this game against the Raptors and try to fix them when we go out and play Boston."

After the Celtics, the Grizzlies conclude their regularly scheduled seeding slate Thursday against the Milwaukee Bucks. Securing the No. 8 spot for the seeding game would be critical -- that team will only need to win Saturday while the No. 9 team also would need to win a rematch Sunday to steal the playoff spot.

If there's anything that could provide solace for Memphis in the loss to Toronto, it's fighting back from 18 down to get within single digits of the defending champs by the contest's end.

"I thought our guys brought it today, and we learned a lot in this game against an aggressive defense," Grizzlies coach Taylor Jenkins said.

The Celtics (47-23) don't figure to be a pushover despite having the No. 3 seed locked up in the East. Boston has won three straight, including a hard-fought, 122-119 overtime victory over the Orlando Magic on Sunday.

In that contest, Gordon Hayward scored 31 points on 12-of-18 shooting and added nine rebounds as the offense played off his aggressive performance.

"When he's attacking, we're better because he just makes a lot of great reads with the ball," Celtics coach Brad Stevens said.

Guard Kemba Walker showed he's still shaking off the rust, finishing with four points on 1-of-9 shooting. He played a personal bubble high of 32 minutes as he looks to get past a sore knee.

Boston ends its seeding slate with a matchup against the Washington Wizards on Thursday. After that, the Celtics will wait to learn if their first-round playoff opponent will be the Miami Heat, Indiana Pacers or Philadelphia 76ers.