Celtics guard Marcus Smart will miss Boston’s game against Philadelphia on Friday after being placed in the NBA’s health and safety protocols. Charles Krupa/Associated Press

The Celtics will be without their starting point guard Marcus Smart for their second consecutive game after the veteran was placed in the NBA’s health and safety protocols before Boston’s game against Philadelphia on Friday night.

Smart missed Wednesday’s win over the Pacers with a thigh contusion but was on track to return from the injury for Friday’s matchup against the 76ers. However, Smart became the 15th player on Boston’s 17-man roster this year to enter protocols. Smart also tested positive for COVID-19 back in 2020.

Smart has been one of Boston’s most reliable contributors this season, playing in 38 of the team’s 42 games, while averaging a career-high 34.1 minutes per game. The Celtics are 1-3 in games Smart has missed this year with the only victory coming Wednesday against the Pacers.

With Smart out of the lineup, Dennis Schroder will continue to see starts at point guard in all likelihood, while there will be opportunities off the bench for Payton Pritchard and other young reserves to fill in the remainder of his minutes.

“Obviously Dennis has been in that role all year when Jaylen or Jayson was out or Marcus just missed a game or two,” Coach Ime Udoka said earlier this week. “So obviously we feel like we have another guy that’s basically a sixth starter. Payton coming back is obviously welcomed as far as that, and then what you saw in the last game was Josh Richardson playing some point guard toward the end defensively as well as handling the ball, initiating offense. And you always have Jayson and Jaylen that are touching the ball a ton and guys can play off them.”