Anytime you have a new quarterback under center making his first NFL start, it simply isn't fair to expect he or the offense in general to have a very productive day. The good news in Cincinnati is they have dominated in the trenches on both sides of the ball for much of this season, making it easy for whoever is under center to find enough success to pull out a win.
The defense has been especially dominant as of late with Geno Atkins back to his All-Pro self while defensive ends Michael Johnson and Carlos Dunlap are generating excellent results as well. Those three have combined for 23.5 sacks this season, 3.5 more than the Bengals as a team had in 2014.
Atkins, Dunlap and Johnson must dominate in Sunday's matchup with a 49ers team that's struggling mightily to protect their quarterback. Through 13 games, San Francisco has allowed an unheard of 45 sacks, the most of any team this season. They're on pace to allow 55 this season, which would be tied for the sixth most allowed in one season since 2007.
Making matters worse for the 49ers is that one of the men that would have helped stop Geno is now likely done for the year. Starting guard Alex Boone will miss this week due to a sprained MCL, and he was easily the 49ers' best interior blocker.
With Boone out, starting center Marcus Martin will likely moved over to the left guard spot with Daniel Kilgore taking over at center. That's the alignment San Francisco used Sunday against the Browns, a game in which the 49ers allowed nine sacks to a Cleveland defense among the worst in the league.
It also helps that San Francisco's ground game has fallen off a cliff this season compared to what it was with the mobile Kaepernick under center. They now rank 21st in rushing offense at 96.9 yards per game on the ground, and they're averaging a mere 80.25 rushing yards over their last four games. They'll go against a Bengals' defense that's quietly risen to eighth in rushing defense while giving up just six rushing scores this season, tied for the third-fewest of any team.
But the 49ers' struggles in the trenches are also on the defensive side. They enter Week 15 with the second-worst rushing defense after allowing the Browns to rush for a season-high 230 yards (most in 5 years) after entering Week 13 with the league's worst rushing offense. Over their last four games, the 49ers are allowing 181.3 rushing yards per game.
Given the Bengals will be under the control of McCarron in his first NFL start, they must establish the ground game in order to keep the pressure from being solely on the second-year quarterback's shoulders to win this game. The potential for a monster game from Cincinnati's ground game is certainly here, and this could be where the offense has its most success on Sunday.
In fact, this may be the best chance the Bengals get in the final three games to really establish their ground game, something they haven't consistently done this season. They enter Week 14 ranked 14th in rushing offense and 17th in yards per rush (4.0) while having a 100-yard rusher in just one game this season (Giovani Bernard vs Chargers in Week 2). They've also had a rusher fail to top 80 yards 10 times this season.
Whatever happens Sunday, it's hard to see them winning without dominating the trenches on at least one side of the ball. It could be the defense terrorizing Gabbert and shutting down the run game en route to a defensive struggle with neither team topping 20 points. It may also be a game where the Bengals rushing attack controls the game and allows them to run away with a big win.
Either way, the Bengals need a win, and the trenches are where their best chance of winning this Sunday will be.