SANTA CLARA, Calif. -- The clock started ticking on March 26, 2021, when the San Francisco 49ers traded with the Miami Dolphins for the No. 3 pick in the NFL draft.

It sped up when the Niners used that pick on quarterback Trey Lance on April 29.

And now, despite quarterback Jimmy Garoppolo and the 49ers best efforts to delay the inevitable, the top half of the hourglass is almost out of sand. Barring a significant change of course, his time with the Niners is almost up.

When that happens, it will end a five-year run full of ups and downs and usher in the start of the Lance era.

But before we get there, it's worth taking a closer look at how we got here, the implications of such significant change at the game's most important position and how it could all play out.

Why are the 49ers likely to trade Garoppolo?

The Niners made it clear they were ready to move on from Garoppolo when they traded three first-round picks and a third-round choice to move up nine spots in the draft for Lance. There were multiple reasons, but at the top of the list was Garoppolo's injury history.

For a team that rightfully believed it was in a Super Bowl window, the idea of losing another season because of below-average quarterback play was no longer tolerable. Garoppolo missed 13 games with a torn ACL in his left knee in 2018 and 10 more in 2020 because of ankle injuries. In 2021, he missed two games, one with a torn ligament in his right thumb and another with a calf issue.

"We've had Jimmy here for five years and he's got to play in two of those seasons fully," coach Kyle Shanahan said. "And before this year, it was only one out of four years, and that was our big worry going into it, that we could not go into another year where he didn't make it through."

Of course, injuries aren't the sole reason for the change. Garoppolo has mostly played in line with league averages in the nearly two full seasons he was the starter, but his postseason numbers have been underwhelming (four touchdowns, six interceptions and a 49.3 QBR in six games) and his penchant for costly turnovers lingered.

The Niners have come close to winning a Super Bowl with Garoppolo twice -- and that counts for a lot -- but in both postseason defeats, the primary takeaway was that Garoppolo was good enough to knock on the door of a Lombardi trophy but not good enough to burst through it.

Is there any chance Garoppolo stays with the 49ers?

Despite Shanahan and general manager John Lynch alluding to the possibility, it's undoubtedly a long shot. Garoppolo said he'd "never close every door completely" but sounded the part of a man on the way out in his postseason Zoom news conference on Tuesday.

"It's hard to put all the scenarios into play right now, but I think those things will work themselves out," Garoppolo said. "We'll see what happens, I guess."

When will a trade happen?

There's no set deadline, but it makes sense for all parties to try to have something in place by the time the new league year starts March 16. Getting a trade done by then would allow the Niners to know how much salary cap space they have to work with and give the team acquiring Garoppolo a chance to work out a contract extension so it could also handle additional offseason business.

Trades can't be official until that day but they can be agreed to, which seems like a strong possibility in this instance since it would bring needed certainty for all parties.

What are the salary cap ramifications of a trade?

Garoppolo is slated to count $26.905 million against the Niners' cap in 2022. Parting ways with him would save $25.505 million with $1.4 million in dead money.

The acquiring team would inherit that $25.505 million and would likely want to work out an extension first. Yet another reason for a deal to get done sooner than later.

Who could be interested?

Among the teams who have a clear need at quarterback: Pittsburgh, Washington, Denver, Carolina, New Orleans, Houston and Tampa Bay. Minnesota, Las Vegas and Indianapolis could also decide to make a change.

Depending on what happens with the likes of Aaron Rodgers and Russell Wilson, Garoppolo could be one of the best quarterback options in a market where demand far outweighs supply.

That so many of those teams have playoff-caliber rosters with even a middle-of-the-road quarterback should mean plenty of interest in Garoppolo, especially if they can make the necessary contract adjustments.

While Garoppolo's no-trade clause is technically active, it won't be when a trade could become official. Still, he's likely to have some input in where he lands.

"I just want to go to a place where they want to win," Garoppolo said.

If the Niners do follow through on doing right by Garoppolo, a team like the Steelers, coached by Mike Tomlin, a close friend of Shanahan's, would make plenty of sense.

What will the 49ers get back?

Much of this will depend on who else comes available either in trade or free agency and how the league views what is widely considered a down year in the draft for quarterback prospects.

Mike Tannenbaum, ESPN's NFL front office insider and former New York Jets general manager, believes about a dozen teams will need a quarterback in the offseason, which means San Francisco can fetch a second or third-round pick for Garoppolo.

That could come with an additional, future mid-to-late round pick but would depend on the number of teams involved in the bidding.

"He's a starting NFL quarterback," Tannenbaum said. "He's not worthy of a first rounder but there's a lot of teams that will look at him and say he upgrades us at the most consequential position."