By Cody Westerlund–

CHICAGO (670 The Score) — Bulls big man Lauri Markkanen’s back has flared up again.

Markkanen will sit out against the Celtics on Monday night because of back soreness that he experienced after shootaround earlier in the day, coach Fred Hoiberg said. It will be Markkanen’s first missed game of the regular season. He missed the first three preseason games in early October with back soreness.

“Something that was very similar to something that he had in the preseason,” Hoiberg said.

The plan is for Markkanen to receive treatment Monday evening and Tuesday. The Bulls next play on Wednesday, and his status is uncertain at this point.

Markkanen leads the Bulls with 14.7 points and 8.1 rebounds. Niko Mirotic will start in his place. Mirotic won the starting power forward spot in training camp but then lost it when Markkanen shined as Mirotic missed the season’s first 23 games after getting punched by teammate Bobby Portis in practice on Oct. 17.

The Bulls have closely monitored Markkanen’s workload, as he’s averaged 30.7 minutes per game. They’ll continue to do so in an effort not to overload him, citing his busy summer in which he played nationally for his native Finland. Hoiberg responded with “we’ll see” when asked if this back flareup could cause the team to be more conservative with Markkanen.

In other injury news, guard Zach LaVine continues to participate in full-contact practices every other day, often with the Windy City Bulls of the G League, as he’s in the final stages of rehab after left ACL surgery last February. He does lighter conditioning work on the days in between. The goal is for him to start going hard in back-to-back practices in about a week, then return to game action 10 to 14 days after that, Hoiberg said, once again citing early January as his most time frame for a return.