However, luck was on Purdy's side on that play. Wide receiver Brandon Aiyuk came down with the football and the 49ers' first touchdown in what ended up being a 34-3 victory.
Purdy acknowledged that the throw was a mistake.
"The smart decision's probably just continue to run, try to get as many yards as I can instead of putting the ball up like I did," Purdy said after the game. "But I saw B.A. in the back of the end zone, sort of run space, George as well, and I just put it up towards the back and B.A. came down with it. But, yeah, I'm not necessarily proud of that play, honestly."
It was an aggressive decision by the second-year quarterback, and that's one of the many reasons Purdy's head coach, Kyle Shanahan, loves working with the young player.
"I want a guy who gives us a chance to win the game, not a guy who's just hoping everyone else wins it for him," Shanahan said Thursday on Bay Area radio station KNBR's "Tolbert and Copes" show. "That's where you want it to start. But I am not worried at all about Brock not being that guy. Brock makes plays. He lets it rip. He's done that since the first game he got in, in Miami, halfway through, and he's done it every game since.
"So Brock, we have zero concerns about that. Brock, sometimes, if we're down and stuff, he's not going to take what's given because he's going to do whatever he can to make plays to get us back in. So he's everything you want in that aspect. But what's cool about Brock is he does see things. He has that poise ... and he knows when it's a bad play, too."
When Purdy reached the sideline after that play, Shanahan was there, ready to scold the quarterback for the daring decision. However, he couldn't be too critical. After all, the outcome was impressive.
"Oh, my God, we are the luckiest people ever," Shanahan immediately thought. "And that's, to me, what was a little bit bothersome about it, but he doesn't have too many of those. He makes a lot that are kind of there, and he doesn't sit there and think about it all. He doesn't hesitate. He will let a rip, and we expect that from him because he's so consistent with it.
"That one was just a little bit different. But like I said to him, after I got all my words out of the way, I said, 'Oh, and by the way, thank you very much for the touchdown.' We love touchdowns. That's great. If I was a fan, I'd buy his jersey after the play, but you just know that's not going to last too long if you do too many of those. And he doesn't do too many."
Despite occasional moments of concern, Shanahan remains confident in Purdy's on-field decisions and what the quarterback brings to the team.
You can listen to the entire conversation with Shanahan below.