Should 49ers be concerned about QB Brock Purdy’s preseason picks?

Brock Purdy 's feathery, 19-yard completion between two defenders to tight end George Kittle last Friday was the Pro Bowl quarterback at his best — and some might say, his worst.

Purdy's ability to deliver throws to pass-catchers who look covered over the middle of the field is one of his superpowers. And on third-and-6 against the Raiders in the opening quarter of the 49ers ' final preseason game, Purdy somehow fit a perfect spiral over the outstretched arm of dropping linebacker Kana'i Mauga and just in front of safety Jaydon Grant into the outstretched arms of Kittle for a first down.

That play did not go unnoticed by Will Hewlett, a mechanics and performance coach with CORTX Sports Performance in Jacksonville, Florida, and Purdy's private QB coach.

"That dude takes pride in those throws," Hewlett told FOX Sports. "None of those throws are by accident, to the point that other quarterbacks that we work with are like, ‘How do you do that?'

"That ability to place the ball over people and under the next defender is intentional. They're never lucky with him. He is intentionally placing the ball there, and I think that's a special part of his game."

So what's the downside of Purdy's precision passes. Well, they can lead to interceptions if off by the slightest bit. Purdy's picks during training camp practices and in games have been a popular topic of conversation on social media in the lead up to San Francisco's season opener Sept. 9 against the visiting New York Jets .

At one practice during training camp, Purdy threw four interceptions in his final five pass attempts. And while his interceptions jumped from four his rookie year to 11 in 16 starts during his second season, the Iowa State product said the miscues in practice are more about stretching the limits of the offense.

"Now's the time to be trying out some stuff in terms of throwing to some windows and some tight coverages and whatnot," Purdy told reporters. "But you know, I still have to grow. I still have to be better and I'm hard on myself with it. But now's the time to do it."

Entering his first full offseason of workouts as a healthy starter for San Francisco, Purdy spent six weeks training in Jacksonville grinding on his craft before training camp. Those sessions included working with fellow quarterbacks like Caleb Williams , Anthony Richardson and Mac Jones , who also trained with Hewlett.

"They get to work on similar concepts, different routes and talk about how they do it," Hewlett said. "You see all the differences in footwork, and you can't help but be a sponge and learn from one another. It's a really awesome environment."

According to Hewlett, a focus of Purdy's training this offseason was refining his footwork and mechanics so that they sync up with his progressions in Kyle Shanahan's offense.

"Brock has always been an improviser by nature," Hewlett said. "And with quarterbacks who improvise, you're going to get some elite plays and then it might get you off schedule. So I think he wanted to be a little bit calmer, controlled, and on time with his footwork going into the season. So he could play a little bit more in structure with the play to help be on time with certain routes.

"It was really fine-tuning … his technical side — how he's getting into the throw, how he is producing power in the throw, where his feet are and syncing everything all together."

During organized team activities and in training camp, Purdy's focus has been on gaining better knowledge and command of the offense, so that he can be more efficient on game days. That knowledge base is built over time through thousands of reps.

"Everyone wants to learn it or know it like the coach does," Shanahan said of his complex scheme. "But the coaches only know it because we've been doing it for a long time, and we'd sit in that room in a chair and with a slow motion remote and get to go over stuff all the time.

"And players don't get to do that all the time. They have to go work on being an athlete and doing stuff on the field. It's not just all the mind. They have to work on the physical aspect of the game. So, you always hope that they can count on the coach to help bridge that gap."

Purdy also is dealing with his share of adversity when it comes to his playmakers on the field. No. 1 receiver Brandon Aiyuk remains in a contract stalemate with the 49ers that could get even uglier now that the regular season is just days away.

Aiyuk's potential replacement, first-round selection Ricky Pearsall , has been mostly absent in practice due to a shoulder issue. Christian McCaffrey , the engine of San Francisco's offense, has been limited by a calf injury. And No. 3 receiver Jauan Jennings is unavailable due to a groin injury.

But the most important 49er not at practice is left tackle Trent Williams . The 11-time Pro Bowler, scheduled to make $20.9 million this season, is holding out after dropping to No. 5 on the compensation list among tackles.

With Williams out of the lineup last season, Purdy had an 89.0 passer rating and a 5.2 interception percentage, with two touchdowns and four interceptions, according to Next Gen Stats. The 49ers went 0-2 those games.

With Williams in the lineup, Purdy posted a 118.0 passer rating and 1.9 interception percentage, with 29 touchdowns and seven interceptions. Having his blindside protector on the field gives Purdy more time to make explosive plays and take better care of the football, and it also improves the running game.

But whether Williams is on the field for the start of the season or not, Hewlett expects Purdy to keep slinging it.

"If you're not making a couple of throws a game where your balls come up into your stomach, you're not playing quarterback," Hewlett said. "I would be scared if he wasn't throwing interceptions, if any quarterback wasn't throwing some picks in practice. I think it means you're probably not pushing hard enough. You're not learning.

"As long as you're not making the same mistake over and over again, it's all part of the learning process."

Eric D. Williams has reported on the NFL for more than a decade, covering the Los Angeles Rams for Sports Illustrated, the Los Angeles Chargers for ESPN and the Seattle Seahawks for the Tacoma News Tribune. Follow him on Twitter at @eric_d_williams .

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