SANTA CLARA, Calif. -- It didn't take long to figure out the San Francisco 49ers' identity over the past two seasons.

In 2019, the Niners had the makings of a legitimate Super Bowl contender early, built around a dominant defense and a dynamic running game. That identity carried them to within minutes of a Lombardi trophy.

In 2020, the season was quickly defined by injuries, leading to a disappointing 6-10 finish.

Entering this year, it was fair to wonder which of those seasons was the aberration. Were the 2019 Niners still in there somewhere? Or were the oft-injured 49ers of 2020 more the norm?

As the Niners hit this week's bye, the answer is clear as mud. They have showed glimpses of a team capable of contending again, but have also struggled for long stretches.

If one possession in each game had gone a little different, the Niners could be undefeated. They also could be winless.

Instead, San Francisco is 2-3 and in the midst of a three-game losing streak in a season in which every game has been decided by eight points or fewer.

"We could easily be sitting at 5-0 right now," left tackle Trent Williams said. "Obviously, we're not. We're 2-3 but we go back and revisit every loss, you can find some good in that. There were some things where we could have won some games but we didn't take advantage of the situations."

The Niners' chances of righting the ship will come down to finding a way to make the plays that decide games in the waning moments.

The good news is the 49ers haven't been overmatched in any of their games and the schedule could lighten a bit as the season wears on. What's more, receiver Deebo Samuel looks like a breakout star and stalwarts like Williams and defensive end Nick Bosa are at the top of their games.

When coach Kyle Shanahan and his staff perform their self-scout during the bye, they'll see a team that isn't far off and it's worth noting that there aren't seven obvious playoff caliber teams in the NFC ahead of them. All of that is heartening despite three straight frustrating defeats.

"That's the main thing I try to stress to our team, that it's always going to be hard when you lose games in this league," Shanahan said. "But you can't let a narrative become your reality. You've got to watch the tape, you've got to work harder, you've got to get better at all these little details that come down to winning and losing in crucial moments."

Indeed, there are a number of little and not-so-little details that have held the Niners back in the first five games. Among the primary issues are struggles on third down, turnover margin, a lack of big plays and costly penalties.

The 49ers are 24th in the league in third-down conversions, moving the chains on just 35.6% of their opportunities. On the turnover front, they continue to struggle to create takeaways while maintaining a knack for giving it away.

San Francisco is tied for 29th in the league in turnover margin (minus-5) with two takeaways, second-fewest in the NFL. While it's asking too much to think this defense can reach the heights of that 2019 group, getting more takeaways would undoubtedly help close the gap.

"We need more," linebacker Fred Warner said. "If we want to be the defense that we know we're capable of, we've got to keep hunting at it and when they come, they're gonna come in bunches."

After losing starting cornerback Jason Verrett (torn ACL) for the season and missing nickel cornerback K'Waun Williams (calf) during their recent streak of losses, the Niners have been playing musical cornerbacks, attempting to plug and play a combination of journeymen off the street and unproven rookies.

It's a predictable issue for a team that had a glaring need in the offseason but again declined to invest premium resources into the position. That group hasn't been as bad as one might think in terms of raw numbers but also has contributed to the Niners' eight defensive pass interference penalties for a league-most 153 yards.

Still, the defense hasn't really been the Niners' biggest issue. An uneven offense that has struggled at nearly every position has been more maddening. Aside from the opener against Detroit, San Francisco has gotten off to exceedingly slow starts. The 49ers dropped 31 first-half points on the Lions but scored a combined 21 first-half points in the four games since.

Blame for that can be shared. Niners quarterbacks have been contacted 68 times, the most in the league but they have also struggled to generate big plays with only 15 gaining 20-plus yards (tied for 26th).

The 49ers aren't getting much from their draft class early on. Quarterback Trey Lance has flashed his potential but been used sparingly when Jimmy Garoppolo is healthy. Of more concern is that second-round pick Aaron Banks has been a healthy scratch every week even as right guard Daniel Brunskill has had his issues. Third-round cornerback Ambry Thomas looks to be in the midst of a redshirt year and third-round running back Trey Sermon has only contributed when multiple injuries piled up at the position.

It's a lengthy list of problems but if there's a silver lining to it, it's that many of those problems are self-inflicted, which means fixes are possible and must come from within.

"We've got to find a way to do better, and I've got to find a way to get us to do better," Shanahan said. "Going into this bye week at 2-3, there's still a lot of football left to play. We've got to come back and play better than we have."

The fate of this year's 49ers depends on it.