For about half of the first quarter, the San Francisco 49ers looked like they were going to pummel the Seattle Seahawks into submission. That didn’t happen. Not even close. Just about everything that could go wrong did go wrong after a promising start, and the 49ers lost 28-21, with some Trey Lance intrigue in the second half.

Whatever thought there was to the 49ers pressing their advantage and keeping Seattle on its heels, well, it evaporated by the second quarter.

There’s no real planet in which it should have been a tie game by halftime. But Seattle only plays weird games, and the 49ers didn’t seem like they wanted to convince anyone they were a legitimate contender.

It opened with the 49ers’ defense suffocating an elite Seattle offense and the offense opening with a touchdown and gashed Seattle for 198 yards.

But the offense sputtered in pretty embarrassing fashion. Here’s how the drives went following that touchdown opener:

• Touchdown
• Interception
• Missed FG
• Punt
• Punt
• Punt
• Punt
• Punt
• Fumble

And by the start of the second half, Garoppolo’s day was over. He sustained a calf injury at some point in the Garoppolo came out of the game, things fell apart.

Trey Lance got his extended debut, but it was not at all what anyone who’s a fan of the 49ers in any capacity would have hoped for. He looked every bit like a 21-year-old who was not ready to run the offense.

Lance leaned heavily on his feet, and the 49ers’ receivers and offensive line did not look comfortable playing in a “figure it out as we go” type offense. The receivers didn’t seem to be used to running a scramble drill when the play broke down, and the offensive line didn’t seem comfortable adjusting to a mobile quarterback running around for a while behind them.

This is not to blame either of the receivers or the offensive line, just a statement that the offense looked completely disjointed and out of sorts with Lance running it.

And this isn’t all on Lance, either. He came in cold after not playing the first half, with a limited playbook. He had to wait longer than usual due to a refereeing delay and a turnover, which certainly didn’t ease his very jittery nerves.

What went wrong? Here’s a list:

• No Robbie Gould: That missed field goal in the first half? That was kicked by Mitch Wishnowsky. Robbie Gould sustained a groin injury before the game and sat out, leaving Wishnowsky, who hadn’t kicked since college, as the 49ers’ place kicker, with Kyle Juszczyk as the holder. Wishnowsky missed a field goal and an extra point; Shanahan wanted to try for a two-point conversion, but a false start pushed him to kick the extra point.
• Jimmy Garoppolo: Garoppolo threw a bad interception in the first half which ruined an opportunity to potentially go up by two touchdowns. He left some throws out there before getting injured. And it turns out, he’s clearly still the best quarterback on this team at the moment. Yikes.
• Trenton Cannon on special teams: Instead of downing a ball inside the five-yard line, he barrel rolled into the end zone for a touchback. On a later kickoff, he fumbled the ball twice, muffing it initially, then recovering it, picking it up, then fumbling again. Seattle recovered and scored, and it kept Trey Lance off the field even further.
• Injuries, highlighted by Trent Williams: Aside from Gould and Garoppolo, the 49ers sustained a litany of injuries, but the most severe and worrisome is the one to Williams. He left on a cart in the second half, looking emotional and holding his right elbow. He did not return. There was also a hand injury to Alex Mack, but he returned.

But this was really all about Lance. And he clearly had the jitters.

Lance’s first two passes were brutal. He looked extremely nervous, missing George Kittle worse than Jimmy Garoppolo missed Kyle Juszczyk to start the game in Philadelphia two weeks ago on a dump screen. Then Lance stared down Deebo Samuel, who was double covered, and (thankfully) overthrew him.

It’s tough to assess his performance with total accuracy without seeing exactly what he was looking at on every play, but it was evident that he was not seeing things well.

On most attempts, Lance watched the play develop in front of him, holding onto the ball for far longer than is typical in the 49ers’ offense under Garoppolo. He resorted to running most of the time, and it was successful.

What should we make of this debut? Well, he’s a rookie. A 21-year-old rookie who played one year of college football in a small conference and ran the ball quite often there. He then didn’t play for a full year aside from a one-off game, and obviously need many more reps.

His talent is there, but the game looked too fast for him. How long will it take until it slows down for him? Might it only take a few games or, if we’re being realistic, much longer than that?

Right now it seems like it’s worth finding out.

The problem, though, is the 49ers’ roster is one constructed to compete right now, and Lance is, and was always projected to be, a project player. He’s not on Garoppolo’s level, but also has the athleticism to bail himself out from tough situations; Garoppolo probably isn’t good enough for this team to compete right now anyway.

San Francisco is in a weird situation now at 2-2, and could have harrowing prospects if Williams’ injury turns out to be severe. Right now, they look like much more of a project team with a rookie quarterback than one ready to compete in any serious fashion in the toughest division in football.