Well, that sucked.

The Detroit Lions held a commanding 24-7 halftime lead over heavily favored San Francisco 49ers, but frittered it away by being outscored, 27-7, in the second half to fall just short of the Super Bowl in a 34-31 loss on Sunday.

The Lions gave up 27 unanswered points in the second half, largely fueled by failed fourth downs, a fumble, drops and an inability to slow down San Francisco's offense once it got rolling.

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If you can stomach to rewatch these plays, here's how the Lions' lead slipped through their fingers and resulted in yet another painful mark in the franchise's history. Here's how to blow your first Super Bowl appearance ever, in 5 quick steps:

5. Josh Reynolds drop on fourth down

The Lions were still comfortably ahead, 24-10, looking to answer San Francisco's field goal to start the second half, but the drive came to a screeching halt after Josh Reynolds couldn't hold onto a pass past the sticks on fourth-and-2, leading to a turnover on downs at the San Francisco 28-yard line. Dan Campbell, as he has all season, decided to trust his offense in a big spot, but Jared Goff and Reynolds couldn't connect, drastically shifting the momentum. The turnover on downs led to an immediate touchdown.

4. Brandon Aiyuk stumbling catch after a ricochet

It takes a bit of luck to make a Super Bowl. The 49ers found a pot of gold on their second possession of the third quarter, when Brandon Aiyuk hauled in a 51-yard catch from Brock Purdy after his pass hit cornerback Kindle Vildor in the hands, then the facemask. The ball bounced off the silver helmet directly into Aiyuk's arms at the Detroit 4-yard line. Aiyuk then finished the drive off with a touchdown catch after beating Cam Sutton in one-on-one coverage on the goal line. The touchdown cut the Lions' lead to 24-17 with 5:19 left in the third quarter.

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3. Jahmyr Gibbs fumble after botched handoff

Jahmyr Gibbs only lost one fumble throughout his stellar rookie season, and picked the absolute worst time for his second. On the first play of the drive following Aiyuk's touchdown, Goff and Gibbs had a miscommunication on a handoff, according to Goff after the game, and Gibbs lost the ball while trying to spin out of a tackle in the hole, and Arik Armstead recovered for San Francisco at the Detroit 24-yard line. Christian McCaffrey punched in a touchdown four plays later to tie the game at 24 late in the third quarter.

2. Jameson Williams touchdown drop

A flea-flicker was well played by San Francisco, but Jameson Williams still had a chance to catch the go-ahead touchdown on a beautiful ball from Goff. Instead, Williams couldn't corral the catch over his shoulder against two defenders. It was a crucial lowlight for Williams, who otherwise had a good game by scoring two touchdowns, one rushing and one receiving, and came up with a crucial catch through contact to prevent an interception. But yet, Williams will want to have this one back that would've given Detroit the lead again after falling behind, 27-24.

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1. Failed fourth down

Later on that same drive, the Lions decided once again to trust the offense and kept them on the field for fourth-and-3 from the 49ers' 30-yard line with fewer than eight minutes left instead of attempting a potential tying field goal that would've been about 47 yards long. Goff had no one open, scrambled left and his pass downfield fell a few yards short of receiver Amon-Ra St. Brown, resulting in another turnover on downs. The 49ers burned the clock on the ensuing drive and finished it off with an Elijah Mitchell touchdown, giving them an insurmountable 34-24 lead with 3:02 left. The Lions scored one touchdown on a completion to Williams, but failed to recover the onside kick, meaning the 2023 season is now over on a painful note.

After the game, a visibly hurt Campbell said, "I just felt really good about us converting and getting our momentum and not letting them play long ball. They were bleeding the clock out, that's what they do, and I wanted to get the upper hand back. It's easy hindsight and I get it you know, I get that, but I don't regret those decisions and that's hard. It's hard because we didn't come through, it wasn't able to work out. But I don't (regret it), I don't. And I understand the scrutiny, I get it, that's part of the gig. But, you know, it just didn't work out."

[ Lions fans: Celebrate a renaissance 2023 season with a new book from the Free Press. ]

This article originally appeared on Detroit Free Press: 5 plays that led to Detroit Lions collapse and prevented a Super Bowl