With USC in the shadows, could Mike Tomlin leave the Pittsburgh Steelers?

If there is any profession for which stability could be described as fleeting, it's that of a head football coach.

Job security is never guaranteed, and the only way to ensure your spot is racking up wins on a consistent basis.

Look no further than the USC Trojans, one of the most prestigious programs in college football.

Since the departure of Pete Carroll to the NFL in 2010, the Trojans have had five head coaches, with a sixth to come once the team completes a hiring process after this season. One of the names that has been floated is Pittsburgh Steelers head coach Mike Tomlin.

While USC has been a volatile job over the past decade, the Steelers have been the opposite, with stability a staple in the history of the franchise.

The Steelers have had three head coaches since 1969, with Tomlin holding the position for the past 15 years. He has never posted a losing record in any season at the helm and led the team in winning the Super Bowl in 2008 and winning the AFC in 2010. In nine of his 14 full seasons as head coach, the Steelers won at least 10 games.

Given all that, it's understandable why Tomlin immediately shot down rumors of him being linked to the USC job during a news conference after practice Tuesday.

"I don't have time for that speculation," he said. "That's a joke to me. I have one of the best jobs in all of professional sports. Why would I have any interest in coaching college football?"

Now, it's important to note that much of the stability Tomlin and the Steelers have enjoyed in his tenure has had to do with starting quarterback Ben Roethlisberger. Roethlisberger has worked hand-in-hand with Tomlin over the past 15 years, so with the QB on the back end of his career, now could be the ideal time for Tomlin to explore other options.

But former Steeler and Pro Football Hall of Famer Jerome Bettis doesn't see that happening, especially with another future Hall of Fame quarterback likely becoming available in the coming offseason.

With chatter about Aaron Rodgers' unhappiness in Green Bay, Bettis sees Pittsburgh as a potential landing spot for the veteran QB, which would be reason enough for Tomlin to stay put. Bettis explained the situation on "The Herd."

"I can see it, and one of the reasons that I can see it is because every team has a championship window," he said. "This defense is a championship defense. They still have a three-year window of the defense still being playoff- and championship-caliber."

Tomlin has denied that he has any interest in the USC head-coaching position, and for now, his word should be believed.

But stranger things have happened in the NFL.