BOSTON — Among the many subplots between the Celtics and Nets, there’ll be perhaps a unifying factor for a pair of former teammates. The NBA Playoffs will take place during Ramadan this season from April 1 to May 1, which includes the first round. Both the Celtics’ Jaylen Brown and the Nets’ Kyrie Irving have observed Ramadan in past seasons.

That means from sunrise to sunset, those practicing will fast and won’t consume any water or food. That’s a tough task, especially in a playoff series. But they won’t be able to drink water or take in any nutrients until the sun’s down. Brown didn’t specify whether he’ll observe Ramadan during the postseason, saying it’s a private matter, but he talked about what the month has meant for him.

“Ramadan is something special,” Brown said Thursday. “It’s something that’s saved my life in a lot of ways. So shoutout to all the people who are participating and shoutout to everybody who shows respect because, in reality, some things are bigger than basketball.”

Both Irving and Brown have observed Ramadan in past years. Brown has celebrated Ramadan previously and he also fasted a few years ago to help improve his game. Irving spoke about converting to Islam last year and has been more vocal about what it’s like to fast during Ramadan.

There are plenty of challenges that come from observing Ramadan, but it’s also a time of reflection and prayer during the holy month. Both Irving and Brown said their connection to God has strengthened during Ramadan. That’s helped them off the court while also helping their mental strength solidify during the month.

“Ramadan is a special moment, a special time,” Brown said. “Definitely relating your relationship with God and your relationship through adversity, persevering through distractions and any negativity, anything that pulls you away from being your higher self.”

There are other cases of NBA players fasting while still playing basketball at the highest level. Hakeem Olajuwon famously put up numbers during Ramadan, including winning Player of the Month in 1995.

Fans have dubbed Irving with the “Ramadan Kyrie” nickname as he puts up impressive scoring outbursts despite the guard fasting during games. His latest performance was a 34-point outing against the Cavs in the play-in tournament.

“This is a journey between me and God,” Irving said Tuesday after the Nets’ win. “I appreciate the recognition on different platforms, but it’s really sacred to me. It’s protections I feel for my brothers and sisters that are doing the same with me. Just a blessing to be able to do it and still be able to perform.”

The Celtics will open their first-round series against the Nets at 3:30 p.m. Sunday at TD Garden, meaning the sun will still be up during the game. While practicing Ramadan during the playoffs will be tough, Irving and Brown said they feel refreshed mentally, which is an edge they have.

“It’s not easy by any stretch of imagination,” Irving said. “So you can’t really take any moment for granted during the day. I don’t really have time or the attention to give energy to any distractions. So I come in here and I really just pay attention to the details. Remind myself that I’m breathing, and that’s enough.”