SANTA CLARA, Calif. -- The San Francisco 49ers enter the 2020 season with expectations befitting a team coming off an NFC championship.

With 18 of 22 starters and most of their coaches back, the Niners are a clear favorite to make a push for a second consecutive Super Bowl appearance.

But to sustain success in the NFL, you have to navigate new challenges. While the Niners boast a deep and talented roster, they also have their share of questions to answer.

With that in mind, here's a look at some of the things that could derail another 49ers Super Bowl run:

Inside out

While Chiefs quarterback Patrick Mahomes ultimately became the Super Bowl LIV MVP, a real argument could have been made that the best player in that game, at least in the final quarter, was Kansas City defensive lineman Chris Jones. Jones pressured Niners quarterback Jimmy Garoppolo into throwing an interception in the second quarter and batted down three passes that likely would have been big gains for the Niners down the stretch.

While Jones is the type of player who gives even the best lines fits, he exposed a weakness in San Francisco's unit that appeared would need to be addressed in the offseason. Namely, at right guard, where veteran Mike Person retired.

The 49ers didn't have the resources to pour into the position this offseason. They signed veteran Tom Compton to a low-cost deal and planned on a competition between Compton and Daniel Brunskill. Making matters worse along the line, center Weston Richburg is still recovering from a torn patellar tendon and will miss at least the first six weeks on the physically unable to perform list. His backup, Ben Garland, has been battling an ankle injury for most of camp.

Instead of pushing for the right guard job, Brunskill had to take reps at center while the Niners tried to sort things out next to him. That left rookie Colton McKivitz also figuring into the right guard mix.

“You're always concerned about guys who haven't been playing and with the injuries that we've had and stuff at that position, a few others," coach Kyle Shanahan said. "I think we've got an idea of the guys that we want to go with, but we’ve got to see how people heal over this next week or so and who's in the best health and football shape to be ready for next Sunday."

A defensive regression?

For most of last season, the 49ers' resurgent defense carried the freight. A fearsome pass rush punished opposing quarterbacks and created opportunities for the back seven to create turnovers. The Niners finished second in the league in yards allowed per game a year after finishing 13th.

Maintaining that level of defensive dominance has proved difficult -- though not impossible -- for teams finishing near the top of the league the previous season. In the Niners' case, it wouldn't be a surprise if the defense was a focal point again, but it's not going to be easy after trading star defensive tackle DeForest Buckner to the Indianapolis Colts.

Although the Niners have plenty of depth on their defensive interior, replacing Buckner is no easy task, especially with rookie tackle Javon Kinlaw more of a raw prospect than a polished product.

“You can't underestimate losing a player like DeForest," Shanahan said. "He’s as good of a teammate and one of the best players in the league at his position. We feel we have got some guys there and stuff, but that’s not easy to just come in and replace someone like that. So we've got a group of guys, who it's going to take them some time. ... We've got a number of guys who are capable and it’s going to take a bunch at first and hopefully they'll just keep getting better and we can try to fill that void.”

If the 49ers' pass rush struggles without Buckner, the trickle-down effect could reach the secondary and the defense could take a step back, putting the onus on the offense to pick up the slack.

Health is wealth

Yes, this is true for every team. Generally, the teams that have the most luck with injuries are the ones who make it the furthest. But with the added variable of COVID-19, it falls on the players and coaches to hold one another accountable and ensure that the only health issues they face are the ones that come because of injury and not illness.

The new challenge can be found in preventing an outbreak of the virus. The 49ers have had three players land on the reserve/COVID-19 list, the latest of which is star linebacker Fred Warner. It's why Shanahan has continued to emphasize the importance of staying vigilant and his locker room leaders are doing the same.

"I think on a team like ours, we’re uniquely constructed to deal with this because obviously we’re in Santa Clara," cornerback Richard Sherman said. "There’s not a huge night life. It’s not like we’re in Atlanta or Texas or Miami or Las Vegas or L.A. where there’s a lot of distractions, a lot of places you can go, a lot of things you can do to get yourself in trouble. I think our team is incredibly focused because of how close we were to winning the Super Bowl last year. And that taste in their mouths is a bitter discipline in itself. That hunger, that angst, is discipline in itself.

"I think the team that will adapt the best will be the one holding the trophy at the end."