49ers’ strong start vanishes against Denver in 30-9 preseason flop

SANTA CLARA – Patrick Willis, inducted last summer into the Pro Football Hall of Fame, stopped behind a Levi’s Stadium end zone Saturday night and relayed how excited he was to watch live football.

Yes, even a preseason opener that would yield first impressions of a new defensive cast.

So, which of the next-gen linebackers might eventually make plays like Willis did from 2007-14? Stay tuned. We’re only one preseason game into this, and the 49ers’ growing pains showed as a 9-0 lead flipped into a 30-9 defeat against the Denver Broncos.

That early lead came via the 49ers’ would-be backups against the Broncos’ legitimate starters, however.

“I felt pretty good with the defense in the first half,” coach Kyle Shanahan said. “Mental mistakes kept a couple of drives going. I didn’t feel a lot with pass rush out there but have to watch the tape for sure.”

All-Pro Fred Warner got the night off with most other of the 49ers’ projected regular-season starters. But Dee Winters, Warner’s wingman in the starting lineup throughout camp, did play the opening two series as the weakside linebacker next to Tatum Bethune, Warner’s impressive understudy.

“Dee is going into his third year, but this is really my first year seeing him. Man, it looks like he’s hungry and ready to take that next step,” Willis told the Bay Area News Group. “Obviously it’s all about doing it. It starts with the will to want to, and he’s been practicing his tail off and looking good. I see a lot of upside to him.”

Winters didn’t have a tackle in the 10 snaps over the opening two series, but he’s had an otherwise impressive camp through 12 practices.

Another option next to Warner is Nick Martin, a third-round pick who replaced Winters Saturday night. Martin had multiple missed tackles in the third quarter, with one open-field whiff nullified by a Broncos penalty. Shanahan acknowledged those gaffes, including his coverage on a third-down shallow cross, but otherwise praised Martin’s camp and learning opportunities that await.

“Nick, when you’re a freshman, the only thing you can do is show up each day and work your tail off, and he’s been doing that,” said Willis, who attended Thursday’s joint practice against the Broncos. “Obviously there’s things we can always get better on, and it’s a matter of just working on those things.”

Martin’s late coverage allowed a touchdown catch to tight end Caleb Lohner with 2:15 left.

“He’s going to be very valuable. Special teams is really going to need him,” Willis added in pregame about Martin. “And then when you get a chance to come in on third downs, make a play here or there, but most important, be sound and get the confidence of your teammates you can do the right thing.”

Bethune made three tackles on Saturday’s opening drive, and he returned to action in the second quarter after treatment on his right ankle. Willis was aware of him beforehand: “Bethune, I really feel could be that third linebacker and step in and be someone they can trust to get the job done.”

The 49ers, of course, have a void to fill next to Warner because Dre Greenlaw left in free agency for the Broncos; a quadriceps strain kept him out of action against his old team in practice and this game.

“I don’t think you can just replace someone like Dre Greenlaw,” Willis said. “But when you have someone like Fred, all you need is someone beside you that you’re confident they’ll be where they’re supposed to be.”

For Willis, that sidekick became NaVorro Bowman, and they helped lead the 49ers to three straight NFC Championship Games and a Super Bowl in Willis’ final three full seasons before foot issues prompted his 2014 exit.

From the first night they roomed together in camp at the Santa Clara Marriott, Willis knew Bowman would be a perfect fit, because Bowman didn’t need Willis’ advice to dive into the playbook. “I’ll never forget, true story, I walk in our room and he’s already in his playbook,” Willis said. “It hit me right away. The rest is history. We chopped it up and I won’t tell you the things we talked about, but I was, ‘I think we’re going to be alright.’ ”

EARLY LEAD

Once Winters and the 49ers defense took the field, they had a 7-0 lead to protect, courtesy of a game-opening drive that culminated in Patrick Taylor Jr.’s 5-yard touchdown run.

Mac Jones, starting at quarterback in place of Brock Purdy, had a fourth-and-1 conversion plunge on the preceding snap, and Jones really sparked the drive with a 50-yard completion to rookie Jordan Watkins to the Broncos’ 16-yard line, where former 49ers safety Talanoa Hufanga made a touchdown-saving stop.

Jones went 4-of-7 over three series, with his final pass intercepted when Ja’Quan McMillan undercut an out route by Watkins in 49ers’ territory. Carter Bradley took over early in the second quarter and threw an interception on his second series.

DEFENSE’S DEBUT

In Robert Saleh’s return as defensive coordinator after four years away, his unit produced points on its second series. Nickel back Chase Lucas’ blitz forced Bo Nix to retreat into the end zone and throw the ball away toward the sideline, resulting in a safety and 9-0 Niners lead.

Then the Broncos scored 20 unanswered points before halftime, including touchdown catches against starting cornerbacks Darrell Luter Jr. and Dallis Flowers. Luter’s apparently blown coverage allowed tight end Lucas Krull to get wide open for an 8-yard scoring catch, then Jarrett Stidham found ex-49er Trent Sherfield for a 36-yard touchdown over Flowers.

Earlier, the Broncos settled for field goals thanks to a Luter pass defense in the end zone against Courtland Sutton, then sacks on the next series by Robert Beal Jr. and Kalia Davis.

INJURY UPDATES

Marques Sigle, a rookie starter at safety, recorded seven tackles before sustaining a first-half knee injury that Shanahan believes is a bruise. “He flashed a lot tonight. He got a late start. A few days into camp was when he got going,” Shanahan said. “He had a heck of a week and finished it off today.”

Sigle started next to veteran Jason Pinnock while the 49ers were without a trio of starters from last season — Ji’Ayir Brown (ankle), Malik Mustapha (knee) and Hufanga.

Running back Ameer Abdullah sustained a rib injury while fumbling on a third-quarter run. Defensive end Robert Beal Jr. strained his groin in the fourth quarter.

Defensive lineman Mykel Williams indeed sustained a left-knee hyperextension and may need only one more week to recover, Shanahan said.

JENNINGS’ CALF

Shanahan insisted that wide receiver Jauan Jennings’ absence the last two weeks is due to a calf injury, similar to one he had not only in the spring organized team activities but also last training camp. Asked if Jennings told him he’s holding out for business purposes in quest of a contract extension, Shanahan replied: “Not at all.” Jennings was the first player to exit the locker room after Saturday’s game.

MOST STARTERS SHELVED

Healthy scratches on offense were Purdy, Christian McCaffrey, Kyle Juszczyk, George Kittle, Rickey Pearsall and linemen Trent Williams, Jake Brendel, Dominick Puni and Colton McKivitz, along with injured wide receiver Jauan Jennings (calf). Ben Bartch started at left guard, where the 49ers have him pegged to replace Aaron Banks (Green Bay Packers).

Defensively, the 49ers sat Warner, Nick Bosa, Mykel Williams (knee), Jordan Elliott (back), Kevin Givens (pectoral), Renardo Green (hamstring), and Brown (ankle). Rookie nickel back Upton Stout did not suit up because of a tight calf.

Shanahan said 19 didn’t suit up because of injuries and seven were healthy scratches.

The Broncos played their usual starters, including defensive linemen Nick Bonitto and John Franklin-Myers, who had sacks on the 49ers’ second series.