SANTA CLARA — So many holes exist on the 49ers’ stripped-down defense that they overshadow an annual question.

Is it time to draft an offensive tackle in the first round?

Five years ago, the 49ers made a seismic shift at left tackle on draft weekend. Joe Staley, one of their all-time best first-round picks, retired after 13 seasons. That prompted the then-reigning NFC champs to spring Trent Williams out of Washington’s clutches.

This draft, the 49ers might need to execute another succession plan and find Brock Purdy’s next blindside protector — or perhaps a right tackle who challenges incumbent starter Colton McKivitz. They’re on the verge of committing long term to Purdy with a record contract, so protecting that investment in a long-range model seems logical.

But which offensive tackle? And can they wait until pick No. 11 to get him?

“There are not a lot of people that have the skill set to play tackle, so it reduces the (candidate) pool, and also they typically go pretty early,” Tariq Ahmad, the 49ers co-director of player personnel, said after last year’s draft. “We are very selective of those guys.”

Last year, eight offensive tackles were selected in the first round, and three by pick No. 11. The 49ers did not select until No. 31, where Ricky Pearsall became the sixth wide receiver off the board.

In Round 2 last year, once tackles were taken by the Houston Texans (Blake Fisher, No. 59) and the Baltimore Ravens (Roger Rosengarten, No. 62), the 49ers traded out of No. 63 and down a spot with the Kansas City Chiefs, who took left tackle Kingsley Suamataia (and subsequently benched him after two starts).

The 49ers spent their second-round pick on cornerback Renardo Green, and they did eventually draft two versatile linemen: Dominick Puni (third round; a 17-game starter at right guard in 2024) and Jarrett Kingston (sixth round; waived after the preseason).

Williams’ longevity is in question after he, at age 36, missed the final seven games last season with an ankle injury. General manager John Lynch has indicated that Williams’ health is much improved — and so will be the 49ers offense. But with understudy Jaylon Moore leaving in free agency, the 49ers need a new backup and/or successor, all while McKivitz is entering his contract’s final year.

Williams held out for a three-year, $83 million contract into Week 1 last season, but that wasn’t seen as a golden parachute into early retirement for three straight All-Pro seasons. “At my age, I know there are not a lot of people who’ve played at an All-Pro level outside of a quarterback. I want to bust those barriers and show this is a new age,” Williams said. “… But Father Time is undefeated, as we’ve seen.”

Offensive tackles are pricey. Getting one in on a rookie contract would work in harmony with this offseason’s roster shift.

When the 49ers are on the clock this draft, here are offensive tackles who could entice them:

Kelvin Banks Jr. (Texas), 6-foot-5, 315 pounds: The native of Humble, Texas, won the Lombardi Award and Outland Trophy as a third-year starter. His 20-yard shuttle time (4.66 seconds) was the second-fastest among tackles at the combine.

Will Campbell (LSU), 6-6, 319 pounds: The All-American and three-year starter has drawn concerns with his 773/8-inch wingspan and 325/8-inch arm length. His ahleticism showed in his broad jump at the combine (9 feet, 5 inches).

Armand Membou (Missouri), 6-4, 332 pounds: Membou started 27 games at right tackle at Missouri. His athleticism wowed at the combine, including the best 40-yard dash (4.91 seconds; 1.74-second 10-yard split) and most bench-press reps (31) among tackles.

Josh Conerly Jr. (Oregon), 6-5, 311 pounds: A childhood Seahawks fan, he ran the fastest 10-yard split (1.71 seconds) among O-linemen at the NFL combine, where the 49ers formally met with him before they sent a five-man crew to Oregon’s pro day.

Josh Simmons (Ohio State), 6-5, 317 pounds: A San Diego State transfer, he moved to left tackle in 2023 at Ohio State and tore the patellar tendon in his left knee last season, so the 49ers could be scared off from an injury they saw with Weston Richburg, Mike McGlinchey and Drake Jackson.

Roll call: Aireontae Ersery (Minnesota), Ozzy Trapilo (Boston College), Anthony Belton (NC State), Marcus Mbow (Purdue), Wyatt Milum (West Virginia), Jalen Travis (Iowa State), Jalen Rivers (Miami), Brandon Crenshaw-Dickson (Florida), Jonah Savailnaea (Arizona), Logan Brown (Kansas)