With just four yards of offense in the first half for the Chicago Bears against the San Francisco 49ers in Week 14, Thomas Brown and his team reached a low that hasn't been met since at least 2000, per Kevin Fishbain of The Athletic on X.

“The Bears' 4 yards is their fewest in a first half this millennium, per @TruMediaSports,” Fishbain wrote.

However, this wasn't where it ended for the Bears' historically poor performance in the first half against the 49ers, per Nate Tice on X.

“The Bears just averaged .2 yards per play in the 1st half against the 49ers,” Tice wrote. “This is the 3rd-lowest average yards gained in a 1st half by any NFL team since 2012, per @TruMediaSports.”

Once the final whistles blew in the first half, the Bears had four total yards, while the 49ers were over 300 yards of offense. To say it was a lopsided first half would be a massive understatement.

In fact, it was a historically bad first-half performance by Brown in his head coaching debut for the Bears.

Bears interim HC Thomas Brown struggling in debut vs. 49ers

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Chicago Bears interim head coach Thomas Brown stands on the sideline during action against the San Francisco 49ers in the first quarter at Levi's Stadium.
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With the opportunity to end a 1,078-day streak for the Bears, the offense came out as flat as they have in nearly their entire existence.

Brown— the team's passing game coordinator turned offensive coordinator turned head coach— had by Bears fans thinking he could be the potential answer for their coaching vacancy once Matt Ebeflus was fired. However, following the first half of his debut, it appears the Bears will be going all-in on Ben Johnson this offseason.

Maybe Brown can do what Eberflus rarely did by making crucial second-half adjustments. Brown doesn't present himself as someone willing to give up, so it'll be telling to see how his Bears look in the second half.

However, with just one half under his belt as the team's stand-in head coach, it could take time to see his flowers bloom. When listening to Brown speak since becoming the Bears' head coach, he appears to demand a high level from his players.

Following their historically bad first-half performance, Brown has a lot of adjustments to make in the second half.