CHICAGO -- Following his team's disappointing 19-10 loss to the Chicago Bears on Sunday, San Francisco 49ers quarterback Trey Lance stepped to the podium prepared to shoulder the blame.

The first query had barely been lobbed his way before Lance immediately began rattling off all of his mistakes in the defeat. The list: overthrowing wide-open tight end Tyler Kroft for a would-be touchdown, an interception to Bears safety Eddie Jackson, taking a sack that knocked the Niners out of field goal range and missed third-down throws to receivers Deebo Samuel and Jauan Jennings.

"Just too many mistakes on the field," Lance said. "I’m just frustrated with myself a little bit. I just feel like I'm a lot better than that."

Lance finished 13-of-28 for 164 yards with no touchdown passes and an interception for a passer rating of 50.3. He also ran for team highs in carries (13) and rushing yards (54). The Bears were content to force Lance to beat them from the pocket, as they didn't blitz him once in his 34 dropbacks. He's only the seventh quarterback in the past 15 seasons to drop back 30-plus times and not face a blitz. Quarterbacks in such scenarios are 1-6, according to ESPN Stats & Information research.

Of course, the Niners entered this season knowing Lance would have his share of growing pains, but it was also hard to judge him (or anyone else) much on a day when the rain never stopped and the playing conditions were more akin to a Slip 'N Slide than a football field.

"Absolutely not," right tackle Mike McGlinchey said. "Not in those conditions. I would never hold any of that against him. But as for our performance as a team, the game shouldn't have been in that position in the first place."

That was a sentiment shared throughout the Niners' locker room after coughing up a 10-0 lead in a game they seemed to have under control. For most of the first three quarters, it appeared as though the Niners were going to dispatch the Bears with relative ease. But with every opportunity the 49ers' offense had to extend the lead, they made a costly mistake in the form of a penalty, a turnover or a combination of the two. While the offense was failing to capitalize on those chances, the defense kept making the type of miscues that allowed the Bears to hang around.

San Francisco finished with 12 penalties for 99 yards and two turnovers while going 1-for-3 in the red zone. Chicago had three penalties for 24 yards and one turnover while scoring touchdowns on both of its red zone trips. The Niners' mistakes were spread almost equally, with four penalties on offense, six on defense and two on special teams.

The timing of some of those infractions was equally costly. The Niners had three defensive penalties on third down for 45 yards, all three resulting in a Bears first down. Two of those kept the Bears' first two scoring drives alive.

"It's hard enough to play against the opposing team," left tackle Trent Williams said. "It’s even harder when you play against yourself. I have been playing football a long time. Any game that I could remember where we had close to 100 yards in penalties, we had two turnovers, especially one in scoring range in the red zone, it generally never turns out that well."

Now, the Niners must figure out how to fix their many issues before Week 2 against the Seattle Seahawks. Opening games against the Bears and Seahawks were supposed to be a relatively light introduction for Lance as the starter, but Sunday offered a reminder that there's no such thing as a sure thing in the NFL.

In theory, the 49ers should be able to fix many of their penalty woes. After all, many of them -- such as linebacker Dre Greenlaw's 15-yard face mask flag -- were the result of a bad decision and not a 50/50 call left in the hands of the officials.

That's no guarantee, given that costly penalties have been a persistent problem for the Niners in recent years. In 2021, the 49ers had the third-most penalty yards in the league (1,066), and they have the 11th-most penalties (539) in the league since coach Kyle Shanahan took over in 2017.

But with Lance learning from his mistakes on the fly, the 49ers can't afford to make things harder on themselves, or a promising season could slip away as quickly as Sunday's game did.

"It's tough to win when you do that stuff," Shanahan said. "We always talk about doing right longer. I think today was the exact opposite of that."