San Francisco quarterback Brock Purdy walks off the field after the 49ers lost to the Kansas City Chiefs in Super Bowl 58 in Las Vegas on Sunday. Carlos Avila Gonzalez/San Francisco Chronicle via AP

LAS VEGAS — For the San Francisco 49ers, another season came a frustrating finish with an inevitable question: What if?

What if the Niners hadn’t botched a punt return to set up a touchdown for Kansas City? What if San Francisco could have converted a third down and run down the clock for a game-winning field goal at the end of regulation? What if the 49ers scored a touchdown on the opening drive of overtime?

And perhaps most importantly, what if the Niners didn’t have to run into Patrick Mahomes and the Kansas City Chiefs in the Super Bowl again?

“I was speechless,” defensive end Nick Bosa said about his mindset following a 25-22 overtime loss to Kansas City in the Super Bowl on Sunday. “There’s not really much to say at this point. It’s going to hurt. It’s going to hit in waves. But that’s life.”

It’s becoming an all-too-familiar feeling for the 49ers. They blew a 10-point lead in the fourth quarter of the Super Bowl for the 2019 season and lost to Mahomes and the Chiefs when one key stop or big completion could have changed that outcome.

They then squandered another 10-point lead in the fourth quarter of the 2021 season’s NFC title game against the Rams when a dropped potential interception by Jaquiski Tartt proved costly.

Then an elbow injury to Brock Purdy on the opening drive of the NFC championship game last season in Philadelphia ended that season.

Now a team with 62 wins in past five regular seasons and playoffs has no title to show for it.

“It just hurts,” Purdy said. “We have the team obviously to do it, to win the whole thing, and come up short like that. The way things have been the last couple of years here, everyone wanted it so bad.”

For a while it seemed like this could be the year that the Niners won it all for the first time since 1994. They led 10-0 early on Sunday but then stalled offensively in the third quarter and botched a punt return that set up a short Kansas City touchdown drive.

There was a blocked extra point early in the fourth quarter that kept the Chiefs within three points. There was a batted down pass on third down with less than two minutes to play that led to a field goal and plenty of time for Mahomes to tie the game.

There was a missed blocking assignment on third down in the red zone on the opening drive of overtime, leading to another field goal.

When the defense couldn’t stop Mahomes, it ended up in a loss on a 3-yard TD pass to Mecole Hardman.

“We had every opportunity to win that game, and we didn’t take advantage of our opportunities,” All-Pro linebacker Fred Warner said.

LOOKING BACK

Despite the disappointing ending, the season had many bright spots. The Niners earned the top seed in the NFC thanks to a high-powered offense. Purdy established himself as the team’s franchise quarterback a little over a year after being picked last in the NFL draft.

The offense had several dynamic playmakers, led by Offensive Player of the Year Christian McCaffrey and pass catchers like Brandon Aiyuk, Deebo Samuel and George Kittle.

The defense was strong most of the season led by players like Bosa and Warner.

FREE AGENCY

The Niners have most of their key players from this season under control for 2024, with only four starters from the Super Bowl headed for free agency.

The biggest questions come at defensive end, where midseason acquisitions Chase Young and Randy Gregory, along with Clelin Ferrell, are eligible for free agency. Ferrell, who was hurt for the playoffs, seems the most likely to return after a strong regular season against the run.

The other key player who could head to the open market is safety Tashaun Gipson. But with rookie Ji’Ayir Brown showing flash this season and 2022 All-Pro Talanoa Hufanga set to return from a knee injury, the Niners could withstand that loss.

CATCH A DRAFT

After back-to-back years without a first-round pick, San Francisco will have the opportunity to fill a hole with a premium draft pick at No. 31.

The Niners are projected to have 10 picks on Days 2 and 3 of the draft, including extra selections in the third and fourth rounds.

Adding depth to the offensive line and secondary could be priorities.