The Philadelphia 76ers and the Boston Celtics will face each other for the fourth and final time this season on Thursday. Philly, which lost the last two encounters, could still tie the series with an upset at TD Garden. Tyrese Maxey and Joel Embiid are out, while Paul George is questionable.The defending champs will host the 76ers on short rest. They are coming off a 128-118 win over the Portland Trail Blazers on Wednesday despite playing without Jayson Tatum, Jrue Holiday and Kristaps Porzingis. Payton Pritchard and Derrick White rescued the Cs with 43 and 41 points, respectively.If key Boston players are again sidelined, the Celtics will need their sharpshooting guards to step up versus Philly.Philadelphia 76ers vs Boston Celtics Injury ReportPhiladelphia 76ers injury reportJared McCain (surgery recovery), Tyrese Maxey (back), Kyle Lowry (injury management) and Eric Gordon (wrist) are out. Joel Embiid will sit out the rest of the season. Paul George is questionable because of left groin soreness.Boston Celtics injury reportJrue Holiday (finger) is doubtful for the game against the 76ers. Jayson Tatum (shoulder), Jaylen Brown (illness) and Kristaps Porzingis (illness) are questionable.Philadelphia 76ers vs Boston Celtics Predicted Starting Lineups and Depth ChartPhiladelphia 76ers predicted starting lineup and depth chartStarters2nd3rdQuentin GrimesJeff Downtin Jr.Kelly Oubre Jr.Lonnie Walker IVJared ButlerPaul GeorgeRicky Council IVJustin EdwardsGuerschon YabuseleAlex Reese Andre DrummondAdem Bona Boston Celtics predicted starting lineup and depth chartStarters2nd3rdDerrick WhiteJD DavisonBaylor ScheiermanTorrey CraigSam HauserJordan Walsh Jayson TatumXavier Tillman Sr.Drew PetersonKristaps PorzingisLuke KornetNeemias QuetaPhiladelphia 76ers vs Boston Celtics: Key MatchupsPaul George vs. Jayson TatumPaul George and Jayson Tatum are listed as questionable ahead of Thursday’s matchup. If both are cleared to play, their one-on-one duel will likely be the head-to-head showdown to watch out for.Tatum has been playing at an elite level, which makes it essential for George to step up on defense. He struggled on Sunday against the Denver Nuggets because of shoulder impingement, finishing the game with 16 points. Before the dud versus Denver, he averaged 28.3 points per game in February.Kelly Oubre Jr. will get his chance to shadow Tatum, but George is the natural matchup against Taco Jay. The Philadelphia 76ers can give the Boston Celtics a hiccup if PG13 can slow down the NBA All-Star forward.Jeff Dowtin Jr. vs. Payton PritchardIn a battle between hobbled teams, the reserves could center stage. After erupting for 43 points against the Blazers, the Celtics will try to see if Payton Pritchard can sustain his form. Philly’s two-way guard Jeff Dowtin Jr. could be in the spotlight as Pritchard’s likely main defender. The Sixers will be in trouble if the frontrunner for the NBA Sixth Man of the Year award goes off.Andre Drummond vs. Kristaps PorzingisKristaps Porzingis might remain out due to an illness. But if cleared to play, containing him will be Andre Drummond’s unenviable task. Porzingis will force Drummond out, which could pose a problem for Philly’s defense.Putting a smaller defender on the 7-foot-3 Latvian does not solve the problem because Porzingis could live in the post to take advantage of mismatches. He is averaging 17.5 points in his last two games against the 76ers. Drummond has his work cut out for him.