General manager John Lynch intimated an extension might not come until Williams, who sat out all of last season, plays out this final year of his contract.
"I think the plan was to land him right now and then let the rest kind of work itself out," Lynch said, per ESPN. "I think it's always an advantage when you get someone in the building, on your roster. Now you've got a chance. We'll get a really good look at him. We'll see where the rest of our team is at, but right now we are just ecstatic that we were able to pull it off at a really opportune time."
Just last week, San Francisco brass believed Joe Staley would be returning to man the blind side for a 14th season. The longest-tenured 49er then relayed he was actually leaning toward retirement. That prompted communication with the Redskins. While many figured the 49ers were deciding on which receiver to take with the No. 13 overall pick, they were actually weighing between offensive and defensive tackles.
After grabbing DeForest Buckner replacement Javon Kinlaw at No. 14, they spent some of their draft capital on a trade up in the first round to nab wide receiver Brandon Aiyuk. Only then did they reconnect with the Redskins, who needed more time to assess their options as San Francisco could offer nothing higher in 2020 than the 156th pick.
"We felt like even though we were assuming some risk without the Trent Williams thing being done, that was a risk we were willing to take," Lynch said of the team's Day 1 decisions.
By Saturday morning, Washington finally agreed to unload Williams, after almost a year of discontent, in exchange for the 49ers' fifth-rounder and a third-round pick in 2021. San Francisco then flipped running back Matt Breida for pick No. 153 and selected OT Colton McKivitz, who they were eyeing as a Plan B in the event they didn't get Williams.
"You're losing a great player like Joe at a very critical position, to be able to have everything line up that he was available right then and for us to be able to land him, I think very fortuitous for us, and we're very excited about that," Lynch added.
The 49ers' fortune could also prove to be a division foe's folly. NFL Network's Mike Garafolo reported the Rams were in on the Williams sweepstakes at one point, with Sean McVay planning to move the seven-time Pro Bowl tackle to guard. That proposal didn't progress, per Garafolo, leaving Williams to land in the Bay where he can splash Los Angeles twice a year.
"Thanks for reminding me," McVay told NFL Network's Omar Ruiz. "I need to go drink a couple of more beers."