Jayson Tatum said he is relishing the big moments this post-season after leading the Boston Celtics to a 96-83 win over Cleveland Cavaliers in Game 5 of the Eastern Conference finals on Wednesday.

The third overall pick in the 2017 NBA draft scored 24 points to extend Boston's perfect home record in this season's playoffs, moving them within one win of the NBA Finals, and the rookie has noticed the difference between playing regular and post-season basketball.

"It's like night and day, you can play the same team in four games in a row or seven, there's no secrets out there," he said.

"I've learnt how important every play and possession is in the playoffs. The smallest things matter, we know how tough it is to close out games.

"We've had a couple of situations where guys have hit threes and it goes to over time. You've got to give it your all until there's zero seconds left on the clock."

Tatum also acknowledged he has had to toughen up quickly against experienced rivals late in the campaign.

"It's the playoffs, guys are going to be physical and with me being a young guy, it tends to happen a lot," he said.

"I know it's coming, it's been happening all playoffs, but I've got to fight through it and keep my composure."

The Celtics travel to Cleveland for Game 6 on Friday.