The Pittsburgh Steelers are 4-3, in first place in the AFC North, and their 41-year-old quarterback is playing at a high level – yet the storied franchise faces plenty of questions over their season so far. Why is that? For the fourth consecutive year, the highest-paid defense in the NFL can be found in the Steel City. Yet this year it has been among the most disappointing units in the league, despite the massive price tag and endless stars.The Steelers have one of the most expensive defenses in NFL history, with nearly $158 million committed to that side of the ball this season, yet the results have been overwhelmingly underwhelming.Coming off last the Week 8 loss to the Green Bay Packers, the Steelers’ defense surrendered 30 or more points for the fourth time in seven games, an embarrassing feat that hasn’t occurred since 2003.Ignoring the kneel-down to end the game, the Packers scored on every possession after halftime. They opened the second half with three consecutive touchdown drives.It is the second week in a row that the Pittsburgh defense has been shredded, first by 40-year-old Joe Flacco, and then by Jordan Love.Meanwhile, on offense for Pittsburgh, Aaron Rodgers has been terrific, delivering everything the Steelers had hoped for and more.Yet none of it will matter if the defense can’t stop a nosebleed.In an exclusive interview with talkSPORT, NFL insider Dan Graziano outlined how the rest of Pittsburgh’s season could unfold if they continue to get great quarterback play but horrendous defensive performances.“The Pittsburgh Steelers’ defense is not good right now,” Graziano bluntly stated.Head coach Mike Tomlin needs to fix his defense, and he needs to do it fastGettyThe four-time MVP looks completely rejuvenated in PittsburghGetty“They are living on reputation. The broadcast always starts with, ‘Oh, they’re known for their strong defense.’ This is not that defense.“This is not the Steel Curtain. This is not peak TJ Watt. That defense got old, and there are older players who are not delivering at a high enough level – they are not winning their one-on-one matchups.”Graziano believes that if the Steelers want to make a legitimate postseason run, they will need to play complementary football.And despite Pittsburgh’s lead in the division, the AFC North remains wide open, especially with Lamar Jackson’s return.“I don’t believe the Pittsburgh Steelers have an offense around Aaron Rodgers that can carry them to great things if the defense is not outstanding,” Graziano continued.“And it has been far from outstanding. That’s why I think you see them sliding back toward the pack. The Ravens get a big win without Lamar Jackson, and they still have to play the Steelers twice. They’re only two games behind, in spite of being two and five…Rodgers has been everything Tomlin and the franchise had hoped he would beGetty“I think all bets are off in this division now that we’ve seen Pittsburgh kind of come back a little bit. “If they can’t get some answers on the defensive side of the ball, I don’t think they are at all a sure thing to hold on to that division lead.“If they had beaten Cincinnati in Week 7 on that Thursday night game, they were probably just about running away with the thing.”As Graziano noted, the Ravens still have to play the Steelers twice, which will go a long way in determining the division champion, and the Bengals will travel to Pittsburgh in three weeks for a massive matchup.Everything is still up for grabs.If the Pittsburgh defense doesn’t rise to the occasion and match their quarterback’s level of play, it could be another season without a playoff win for a franchise that has been spoiled for decades.Stay up to date with the latest from the NFL across all platforms – follow our dedicated talkSPORT USA Facebook page and subscribe to our talkSPORT USA YouTube channel for all the news, exclusives, interviews and more