Los Angeles -- With USC spring football practice looming, there is one position that could affect the way the entire defense performs. Perhaps you've forgotten that former All-America defensive lineman Leonard "Big Cat" Williams has left his cardinal and gold gridiron lair.

In case you were wondering what has become of old No. 94, Williams was busy last week wowing the NFL scouts to the point where one expert proclaimed Williams "Hall of Fame material" while another called him a "once in a generation player."

So what happens to a Trojans defense when the possible No. 1 overall NFL draft pick leaves after his junior season to play professionally? Well, if you’re a USC fan, you start sweating bullets or at the very least clutching and manipulating your favorite religious symbol or beads.

This spring practice, all Trojan eyes will be trained on a select number of potential defensive line candidates auditioning for the defensive end position. The complete complement of defensive line spring options will not be in play since there are four highly touted freshmen that won’t arrive until fall camp.

Last season, fans might have gotten a glimpse into the Trojans defense of the future when Williams wasn’t out there, and it certainly left many wearing USC attire feeling mighty queasy. Watching the Big Cat dominate against Nebraska in the National University Holiday Bowl was a reminder who defensive line coach Chris Wilson will be attempt to replace.

Please have some compassion for Wilson because he will be looking to replace a defensive linemen that that some have arguably called the greatest defensive lineman in Trojans history. If there’s a silver lining to the Big Cat’s departure, it’s that all the current candidates saw Williams’s work ethic both in practice and during games, which was also supplemented by his outstanding character and leadership skills.

As for the potential replacements?

It figures that the easy road map for coach Wilson this spring is to insert senior Delvon Simmons alongside starting senior nose tackle Antwaun Woods and senior defensive tackle Claude Pelon.

Another viable candidate could be sophomore Kenny Bigelow, although some think of him more as a nose tackle. A 6-foot-3, 310-pound talent, much has been expected from Bigelow since his arrival from the East Coast. Misfortune during a voluntary post-spring practice workout a month prior to the start of fall camp last season forced Bigelow to undergo surgery for torn knee ligaments.

Another legitimate possibility is senior Greg Townsend Jr., who flashed at times last season after having overcome what seems like a career of injuries. The son of former star Los Angeles Raiders defensive lineman Greg Townsend Sr., it appears that Junior is ready to go.

Now if you’re really patient and the eternal optimistic, there are the rather large, extremely talented, yet inexperienced incoming freshmen. Those national recruits include Jacob Daniel (6-4, 325), Rasheem Green (6-5, 285), Noah Jefferson (6-6, 330), Christian Rector (6-5, 260), and Kevin Scott (6-5, 315), but they won’t arrive until the summer.

Of those incoming summer freshmen D-liners, keep an eye on Green. The Gardena (Calif.) Serra High All-American is coming off season-ending knee surgery, but if he is good to go by training camp, he could be an immediate option.

For now the process of replacing Williams will focus on the players at hand next week. Although the roar of the Big Cat has been silenced through the NFL draft, that doesn’t mean there isn’t another Lion King in waiting.