CLEVELAND - And so the season for Kyrie Irving starts Sunday. With his "I'm back" tweet the other day, Irving is set to make his debut with the Cleveland Cavaliers after breaking his kneecap in Game 1 of last season's NBA Finals against the Golden State Warriors.

Irving's return is beneficial to the Cavs for the obvious reasons, but also because one of his backups, Mo Williams, will be out Sunday against the 76ers due to a thumb injury. How long Irving will go is yet to be seen, but he certainly has a capable backup in Matthew Dellavedova, who has always played well against the Sixers and is becoming one of the better guards at throwing the alley-oops off his drive to the basket.

Hard to believe, but this is already the third time the Sixers have faced the defending Eastern Conference champion this season. It's just another curiosity in the team's early scheduling. This will be the 29th game of the season for the Sixers, and the 17th away from the Wells Fargo Center.

They've already had six back-to-backs, with three of them being on the road and none of them being both at home. They had a six-game, 10-day trip that took them through a different time zone three times and had them go the crazy route of Charlotte-Miami-Minnesota-Boston-Houston-Memphis. And now Sunday it's the third matchup against LeBron James and the Cavaliers (17-7).

The Sixers have played well so far against Cleveland, losing by seven at home and six on the road in games in early November. But the return of Irving might make for a tougher day.

Here's some things to watch for the afternoon contest:

1. The tandem of Jahlil Okafor and Nerlens Noel. It appeared that Brett Brown was toying with the experiment of having Noel at the center spot and Okafor at the power forward position in Friday's loss to the Knicks. When having two bigs on the floor, Brown envisions one of them being able to step away from the basket at the offensive end. While the hope during the summer was that it may be Noel, that seems to have been scratched as he just isn't able to consistently make an outside shot. Okafor can do that a bit better. Also, Okafor seems to have some good passing ability away from the basket. If they can set up some screens off the ball for Noel, that could be beneficial.

2. Perimeter shooting of the Cavs. Coach Brett Brown ripped his team following Friday's loss to the Knicks, in which they trailed by as many as 30 before losing by 10. He said the defensive play on the perimeter has been non-existent. A lot of that has to do with effort, something that also has been lacking a bit from this team lately, which is uncharacteristic. Of course, you have to be careful when closing out on the likes of LeBron Jamaes and Kyrie Irving, as they'll be more than happy to take the ball to the basket to see what they can find there.

3. Brett Brown's rotation. Know that Kendall Marshall and Tony Wroten are back, Brown appears to be experimenting with what he wants to do at the guard positions. Nik Stauskas played just 7 minutes against the Knicks on Friday. Who is backing up Marshall at the point seems to be among Isaiah Canaan and T.J. Covington, although Wroten has said he sees himself as the point guard of the future for the organization. With the losses mounting and playing time trying to be figured out, that is usually a remedy for some unhappy players. Keep an eye on that.