With Marcus Morris injured, Boston Celtics head coach Brad Stevens is prepared to throw rookie Jayson Tatum into the starting line up to face the Cleveland Cavaliers in their season opener.

That means the 19-year-old could potentially have to guard LeBron James at some point during the contest.

Luckily for the Celtics, this is a possibility that the small forward has been preparing himself for.

Tatum has admitted that he's been thinking about guarding the world's best player and has wondered how it will turn out.

"It went good in my head," Tatum said.

The Duke product accompanied his comment with a smile in an acknowledgment that defending King James is almost an impossible task.

Jaylen Brown took on the responsibility last season in the Eastern Conference Finals and was no match for the four-time MVP.

Tatum can certainly lean on his teammate to find out what he can expect, but it'll be a hugely difficult task for any player let alone a rookie making his NBA debut.

Luckily for the youngster, LeBron is a doubt for the game and may not be declared healthy enough to play due to an ankle injury he suffered in the opening days of training camp.

But the number three pick is certainly excited to potentially take to the floor against a player he's admired from afar for a long time.

"I used to watch LeBron on TV growing up and now I'm playing my first game against him," Tatum said.

Even if James plays, the two wouldn't be matched up for large parts of the game as the Celtics newcomer will assume the starting power forward spot and come up against former Boston man Jae Crowder.

But the experience of being in a hostile environment against one of the best teams in the league will be a valuable one for Tatum.

After the two teams contested the conference finals last season, they are being tipped to battle it out for a place in the finals again.

But their offseason dealings has added spice to their clashes and it could become an interesting 'rivalry'.

Kyrie Irving's return to Cleveland is unsurprisingly generating the most attention and there is sure to be a sell-out crowd at Quicken Loans Arena.

The presence of Crowder on the court and Isaiah Thomas off it will also increase the emotion levels on the night.

It is a hugely anticipated encounter and the perfect way to tip off another NBA season.