Brett Brown famously divides the NBA season into thirds — from the start of the season to Christmas, from Christmas to the All-Star break, and from the All-Star break to the end of the regular season. Leading up to the end of the first third of the season, the Sixers have been stretched thin, allowing Brown to look at his team with a more-critical eye.

“You feel the pain of where you just wish that we were better,” Brown said before Wednesday night’s home game against the Knicks. “There’s stuff that I can control and have to do better as a coach, stuff that the roster rears its head and says we might need some help here. Through that vision line, I can feel our pain, I can feel the areas that we need help with the most.”

When the Jimmy Butler trade was completed, the Sixers were left with a roster spot that still remains. And with the absence of Zhaire Smith and Markelle Fultz, the Sixers' most-pressing issue has been made clear to Brown.

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As for the kind of player he would like to see fill that spot, Brown immediately said he would choose defense over everything.

“A perimeter defensive player interests me the most,” he said. “If you box me in, I’d give you that answer.”

Brown added that he would prefer a player who can play perimeter defense while effectively guarding the pick-and-roll and close-outs, which have been problems for the Sixers.

With the team’s lack of depth, a lot of defensive responsibility has been thrust onto the shoulders of Furkan Korkmaz and Landry Shamet, at times to the detriment of the team. Opposing teams have targeted the two inexperienced guards and taken advantage of matchups they feel they can exploit.

“When I judge the team, you’re reminded of the positives of the starting group,” Brown said. “We’re always mindful of how do we improve the second group and what can I do to help them.”

But defensive growth of young players is not something that can be sped up, and the Sixers know they’ll need more to compete in the postseason.

“This team is still fluid, and we get completely what we’re going to need to have available to us when it gets to the playoffs,” Brown said.

Though it’s nearly Christmas, Brown was hesitant to give a full evaluation of his team. One reason is that the next opponents are the East-leading Toronto Raptors on Saturday and the Boston Celtics on Christmas Day.

“I feel like I can make a far-more candid assessment when Christmas comes, because the body of work will be ample enough to accurately give descriptions of offense or defense,” Brown said.