Dejounte Murray has seen his spot in the rotation change multiple times this season (Photo via Twitter)

When it’s difficult to pinpoint the biggest problem with lineups used by the San Antonio Spurs, you know there’s a major issue. From porous defensive crews playing together to two of the team’s best guards hardly playing together to DeMarre Carroll being treated like he’s Mengke Bateer, Gregg Popovich has been making puzzling choices all season long.

Let’s face it: Popovich is not having a good coaching season. Sure, life is different with Tim Duncan now wearing a suit every night and Manu Ginobili and Tony Parker gone — but lacking the Big Three is exactly what the Spurs were dealing with last season when they won 48 games.

San Antonio had roughly the same roster last season as they do now, with the exception of Davis Bertans now being with the Washington Wizards and a $7 million benchwarmer in Carroll being added to the roster. Yet here they sit at 11-16, struggling to put two consistent quarters together, let alone four.

The Spurs have many problems that still haven’t been fully addressed this season, but they all start with who is and isn’t on the floor at any given time. It’s ultimately the players that determine the outcome of games, but putting the wrong mix of those players on the court repeatedly can doom a season.

Jumbling Lineups at Random

It’s safe to say what the Spurs are doing right now is not working very well. Some days, there seems to be a set plan to play guys a certain amount of minutes no matter how poorly they’re playing. Other days, inexplicable lineup changes are made seemingly based on nothing.

For example, on Thursday against the Brooklyn Nets, Marco Belinelli went from recently being out of the rotation to being back in the the thick of the rotation. In fact, Belinelli started the second half in place of Trey Lyles.

Could Coach Pop have made this move to go with a smaller lineup that’s capable of stopping an explosive player like Spencer Dinwiddie, who led the Nets with 41 points? Well, judging by this play where Dejounte Murray literally had to shove Belinelli to get him into the correct position, let’s hope that wasn’t his reasoning.

Granted, Belinelli made a couple key defensive plays late in the game, but these moments are way too few and far between to make up for the baskets he gives up on the other end of the floor.

Popovich has made several other confusing decisions, such as relegating Murray to the bench for a handful of games before deciding to put him back into the starting lineup. While the young point guard handled it well, the unpredictable nature of Coach Pop’s rotation can’t be easy to deal with as a player.

Guys That Should Be Playing Much More

It’s not often you see no one in the starting lineup above 0 in plus-minus in a win, but that happened on Thursday. There are players who are capable of helping the Spurs outscore the opponents, they’re just not being played enough (or at all).

Popovich’s reluctance to give the young guns more time has been a season-long frustration highlighted by two main weapons he continues to holster.

Lonnie Walker IV

Thursday’s game was further indication that it’s time for Lonnie Walker IV to be higher in San Antonio’s depth chart. Against Brooklyn, Walker didn’t make an appearance in the game until 3:06 remaining in the second quarter. The result when Walker finally hit the court was the Spurs cutting a 12-point deficit to six by the half.

After the team’s starters again fell behind by 12 points to start the third quarter, Walker was inserted with 5:22 left before the final frame. The result this time? A two-point lead going into the fourth. There’s a reason Walker ended the game with a +25: he makes a huge difference on both ends of the floor.

It’s getting to the point where seeing Belinelli succeed is a double-edged sword, as it could reinforce the zany idea that he should be ahead of Walker in the rotation in Pop’s mind.

Jakob Poeltl

LaMarcus Aldridge has lost a step or four defensively, which has led to parades to the basket ending with hardly contested floaters or layups. On Thursday, San Antonio gave up 52 points in the paint thanks mostly to Spencer Dinwiddie and Jarrett Allen killing Aldridge in the pick-and-roll.

At 24 years old, there’s no reason Poeltl should be playing less than 19 minutes per game. His ability to clog the lane and contest shots on a regular basis is invaluable on a team that struggles with defense. Still, there are often long stretches where the Austrian is nowhere to be seen while the Spurs dig themselves into another hole.

Poeltl is averaging 2.7 blocks per 36 minutes (to Aldridge’s 2.0) and covering up for a lot of mistakes made by teammates on the perimeter. While he doesn’t offer much offensively, that end of the floor isn’t as much of a problem for the team as a whole.

With matchups against the Los Angeles Clippers and Dallas Mavericks looming this week, it’s time for Popovich to seriously reconsider how he’s using the roster before the Spurs find themselves in a hole they can’t escape.