With much of their roster sporting blazers instead of jerseys and featuring more in the injury report than the box score, the Boston Celtics are leaning on their youngest player and he’s delivering.

Jayson Tatum has looked unlike a rookie all season, but with opportunity now in abundance, the Celtics’ first-year phenom is taking his game to new heights.

Despite just turning 20 a few weeks ago, Tatum had one of his best performances of the season against the star-studded Oklahoma City Thunder in Boston’s 100-99 win on Tuesday.

Sharing the court with four current and former All-Stars – Russell Westbrook, Paul George, Carmelo Anthony and Al Horford – Tatum was arguably the best player in the game as he dropped 23 points, grabbed 11 rebounds and dished four assists to lead the Celtics.

He did it efficiently too by knocking down 8-of-12 shots, including 3-of-6 from beyond the arc, while finishing with a game-high plus-minus of plus-23.

Tatum has caught the attention of opposing stars this season, with George the latest to be impressed by his talent and potential.

“He doesn’t look like a rookie. He looks like a star in this league,” George said.

“He has that confidence. He has that game. He’s in an organisation who is going to let him and help him become a star. It’s special man, we’ll be blessed to see him for many years in this league.”

Tatum has flashed bits and pieces of his game during the year, but his offensive arsenal was on full display against the Thunder.

From rim-rocking dunks, to spot-up 3s, to mid-range jumpers and even a lethal step-back move on Corey Brewer, Tatum put together a highlight-filled night.

He also set his teammates up on multiple occasions, finishing with four assists, which could have easily been more if shots fell.

Boston coach Brad Stevens even put the ball on his hands on their final offensive possession, in which Tatum drove before kicking out to Marcus Morris, who nailed the game-winning 3.

“I said it before: We’re going to just keep throwing him to the wolves and keep going to him in those moments,” Stevens said.

Over his past five games, Tatum is averaging 18.4 points, 6.8 rebounds, 50.0 per cent shooting from the field and 40.0 per cent from long range.

With the Celtics all but locked into the two seed in the East and several players on the mend, Tatum is getting valuable experience carrying a heavy workload.