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The Tulane Green Wave is gearing up for the start of American Conference play on Saturday, but even though the program is four games into the season, there are still plenty of questions remaining on defense. 

Tulane's passing defense has been average at best, while its rushing defense has been abysmal. The unit will be facing a tough test in the Army Black Knights, which boasts the top rushing offense in the entire nation with an average of 334.2 yards per game. Limiting the run is going to be the most crucial part of the entire matchup for the Green Wave, and it will be up to veteran players to prove that the defense is capable of success.

Here's a look at which defensive players could have the biggest impact in the game. 

S Kevin Adams III

Adams has been one of the strongest defensive players for the Green Wave so far this year, amassing a team-high 38 tackles, including 26 solo tackles, through four games played. 

The junior is all over the field, and he's been making as many big plays as he can. While his role in the secondary is vital, the defense should expect Adams to step up and prevent big gains on the ground against a run-heavy offense. If there's one big thing that his game has lacked so far this year, it's creating turnovers — but the team as a whole has only forced one fumble on the year, so there's room for improvement all around. 

LB Makai Williams

Williams has stepped up in a big way this year, and that's been one of the few bright spots regarding the defense. 

The linebacker has picked up 21 tackles and two sacks on the year, as well as a team-leading three tackles-for-loss. He's also been responsible for a few critical third and fourth-down stops and brings some big energy to the program. 

On the cusp of a true breakout campaign, Williams is undoubtedly hungry for a standout performance and an Olive Green and Sky Blue victory. It wouldn't be much of a surprise to see a whole new level of Williams' game emerge on Saturday morning. 

DL Ed Smith IV

Tulane's defensive line needs to be the primary factor in limiting the Black Knights' rushing attack from the start, and that's where a leader like Smith is expected to step up.

The senior has done about as good of a job as anyone at bringing pressure in the backfield, with two tackles-for-loss, one sack and one quarterback hurry to go along with his 14 tackles. The line as a whole has looked a bit lost at times, but Smith can play a big role in getting the unit back on track. 

Smith is the first line of defense against the rush. It's time to play with something to prove. 

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