SANTA CLARA >> Step 1 in the 49ers’ defensive reboot finally came Thursday night, when their first-round draft pick brought in defensive end Mykel Williams from Georgia.

Then again, the first overall step came three months ago with the re-hiring of Robert Saleh as defensive coordinator.

Now, Saleh, thanks to general manager John Lynch and coach Kyle Shanahan, gets a major addition to a defensive front that got leveled by this offseason’s roster purge, which included last month’s release of defensive end Leonard Floyd and defensive tackles Javon Hargrave and Maliek Collins.

“Saleh is back in the building ladies and gentlemen #trenches,” 49ers owner Jed York posted on the social-media platform X, 10 minutes before Williams’ selection was officially announced at 6:24 p.m.

Williams celebrated his selection while surrounded by friends and family at an Atlanta home.

Lynch made a brief attempt to trade up for Williams, whom he never saw play in person but was further won over upon meeting him in an April 7 visit here.

“We liked the totality of the whole process. The film is very impressive,” Lynch said. “Mykel is a big, good-looking kid in every way – he’s big, he’s tall, he’s long, he’s a great athlete, he’s tough, he’s smart, he’s versatile.”

Defensive line coach Kris Kocurek relayed to Lynch that Williams was the best edge setter in college football, and while that trait is key to the 49ers’ desires, his versatility to also play inside is what the 49ers also covet.

“Him being 20 years old but having a maturity and a way about him when he came through here, we felt that presence,” Lynch said. “He’s very comfortable in his own skin.”

Shanahan said he told his wife and kids Wednesday night that Williams was his top choice but didn’t expect him to last until the 49ers’ pick.

“We stuck there and waited for our guy, and we got the guy we wanted,” Shanahan said.

Only two defensive linemen — edge rusher Abdul Carter, at No. 3 to the New York Giants; defensive tackle Mason Graham, No. 5 to the Cleveland Browns — went in the NFL Draft’s first 10 picks before the 49ers landed Williams at No. 11.

Williams (6-foot-5, 267 pounds) does not turn 21 until June 29. He started 17 of 40 games in his three seasons at Georgia, the same state where he was born (Warm Springs). He never had more than five sacks in a season at Georgia, but he labored through an ankle injury last season en route to repeating with All-SEC second-team honors.

“Because of his size, this guy can play on the edge but also down on the tackle. He can be an inside rusher if he needs to be,” former Alabama and NFL coach Nick Saban said on ESPN’s broadcast. “I like this pick. They need somebody opposite (Nick) Bosa.”

This marks the seventh time in 11 years the 49ers banked their top draft pick on a defensive lineman, the predecessors being Arik Armstead (2015), DeForest Buckner (2016), Solomon Thomas (2017), Nick Bosa (2019), Javon Kinlaw (2020) and Drake Jackson (2022).

The 49ers did not draft a defensive end among last year’s eight selections, having instead relied on the free agency acquisitions of Leonard Floyd and Yetur Gross-Matos.

Floyd started all 17 games but got released last month, and that had thrust Gross-Matos into the likely starting spot opposite Nick Bosa, at least before Thursday’s draft.

Williams made an official pre-draft visit to the 49ers on April 7, and seven other teams also hosted him.

The last defensive end the 49ers drafted was Robert Beal, a 2022 Georgia teammate of Williams and a fifth-round pick who’s produced just one sack through two seasons.

The 49ers have been on an annual hunt to find the perfect complement to Bosa. He’s made five Pro Bowls in six seasons and was the 2022 AP NFL Defensive Player of the Year, but he had just nine sacks in 14 games last season.

A year ago, the 49ers were coming off a Super Bowl loss, and they supplemented their receiving corps with No. 31st overall pick Ricky Pearsall.