Photo: Boston Celtics/X

As the Boston Celtics push forward in the playoffs, they’re doing so without a fully healthy Kristaps Porzingis. The veteran center has looked noticeably limited on the court, and now it appears that an ongoing, mysterious illness is at the root of the issue.

Porzingis was forced to exit Game 1 of the second-round series against the New York Knicks early due to illness and was subsequently brought off the bench in Games 2 and 3 – a significant change for a key starter.

According to team sources, this isn’t a new development. The condition appears to be related to the unexplained illness that sidelined Porzingis for multiple games back in March.

Doctors still haven’t identified the exact cause of his symptoms, which have included extreme fatigue and fluctuating stamina. Despite some hopeful signs at the start of the postseason, the issues resurfaced just as the second round began.

“It’s led to him having energy zaps and stamina ebbs and flows over the last couple of months, and he felt that he had actually turned the corner right as the playoffs started in mid-April,” reported ESPN’s Shams Charania. “But in his own words, he had a crash right before Game 1 of this series, and he’s tried a lot of different things to try to mitigate the side effects. I’m told he’s been receiving IVs, immune boosters.

“He’s even changed up his sleep patterns to try to get more rest. He’s essentially waking up every day, hoping and praying that he feels better.”

Despite the setbacks, Porzingis gave the Celtics valuable minutes off the bench in Game 3, logging 19 minutes with 5 points, 4 rebounds, 2 assists, and 3 blocks – showing flashes of his two-way impact.

Still, it’s clear he’s not yet himself, and Boston will continue to monitor his status closely as the series progresses.