SANTA CLARA, Calif. — With just under eight minutes to go in Thursday’s win against the Seattle Seahawks, San Francisco 49ers quarterback Brock Purdy scanned the field in search of a knockout punch.

While Purdy isn’t against such layups, he’d much rather throw the halfcourt alley-oop for a final exclamation point if given the opportunity. Which is why, instead of throwing where Shanahan expected, Purdy let a long pass fly well before receiver Brandon Aiyuk reached a final aiming point amidst four Seattle defenders.

“I couldn’t believe he was throwing it,” Shanahan said. “We’re all holding our breath as soon as he lets it go.”

As it turned out, Purdy’s pass had the perfect amount of touch, as he dropped it over a defender and between three others just as Aiyuk arrived. Aiyuk hauled it in, took on a defender and spun into the end zone for the game-sealing touchdown.

“He does that pretty consistently,” Shanahan said of Purdy. “Very rarely does he check it down and you tell him he missed the deep one. He looks at it that way. He proved to us while the ball was in the air it was the right decision.”

There’s plenty to be said about that throw and Purdy’s growth in his second NFL season, but there’s an equally important takeaway that’s flown under the radar: While Purdy’s decision might have been surprising to everyone else, his connection with Aiyuk made it a no-brainer.

“It’s that trust, that faith in each other,” Purdy said. “What we do every single day at practice and stuff, it’s showing on the field. It feels good.”

On an offense loaded with stars, Aiyuk has emerged as Purdy’s most consistently dangerous and reliable target. It’s no coincidence that Purdy and Aiyuk’s emergences have come simultaneously because their games, in many ways, are ideal complements to each other.

Since Purdy stepped in for an injured Jimmy Garoppolo in Week 13 last year, Aiyuk and Purdy have played 16 regular-season games together. In that time, Aiyuk ranks 12th in the NFL in receiving yards per game (77.8), first in yards per reception (17.3) and yards per target (12.0) and third in yards per route run (2.91) and is tied for second in receptions of 20-plus yards among players with at least 20 receptions (36.1%).

For Purdy, Aiyuk’s route-running and catch radius have instilled belief that no matter who the defender is, Aiyuk is going to be where he needs to be when he needs to be there. It’s allowed Purdy to throw with the type of anticipation that quarterback/receiver combos work years to attain.

“He does it all,” Purdy said. “He’s just one of the most underrated receivers I think in the NFL … I have all the confidence in the world in him and he’s always where he needs to be. As a quarterback, that’s all you could ask for.”

Purdy’s accuracy and willingness to push the ball downfield have allowed Aiyuk to develop into one of the NFL’s most dangerous vertical threats. Aiyuk’s targets and receptions per game are nearly identical to what they were pre-Purdy, but his overall production has increased significantly because the young quarterback ensures that nearly every target comes with a chance for an explosive play.

With Purdy as his quarterback, Aiyuk’s receiving yards per game have jumped 22.2 yards per game, his yards per reception are up 4 yards and his receptions of 20-plus yards have increased 13.9%.

“I just think he has a good feel for how I’m about to run my route on certain looks and where I might end up,” Aiyuk said. “He has a good feel of all the receivers, so I think that helps his accuracy even more because he can feel what we’re doing.”

That feeling hasn’t been easy to attain. Even after a Week 1 outing in which Aiyuk had eight receptions for 129 yards and two touchdowns, he said chemistry with Purdy was still a work in progress.

That work started before the season began. It was clear in training camp that Aiyuk was poised for an even bigger season than the one he had in 2022, as he was often the most dominant player on the field in racking up 78 receptions for 1,015 yards and eight touchdowns. But it’s a commitment to detail that’s allowed Purdy and Aiyuk’s connection to grow in 2023.

Throughout camp, Purdy closely studied the intricacies of how Aiyuk moves, noting that he can cut and move without the choppy steps others might need to get out of a break. That, combined with Aiyuk’s quickness off the line, helped Purdy gather a better understanding of how fast Aiyuk can create separation and buoyed Purdy’s confidence in throwing to spots that he knows Aiyuk can reach before the defender.

Purdy also gained a better understanding of how Aiyuk’s 81-inch wingspan — just one inch less than Hall of Famer Calvin Johnson, who was five inches taller — learning he can take a few more chances when throwing to Aiyuk because he can get his hands on passes that other receivers might not.

For his part, Aiyuk has seen a steady growth in his ability and role since he arrived as a first-round pick in 2020. As 2022 proved, Aiyuk was always going to be a productive receiver despite a few early hiccups. Now that he seems to have stability at quarterback, that should continue.

“I think we’ve gotten to a good spot, just weeks and weeks of working,” Aiyuk said. “That’s where our focus is. Just continue to get better and see where we end up at the end of the year.”

The end of the year will come with additional meaning for Aiyuk. He will be entering the fifth and final year of his rookie contract at a price tag of $14.12 million for 2024. He also figures to be coming off his best NFL season and, perhaps, his first Pro Bowl appearance.

Through 10 games this season (he missed one game and was limited in another with a shoulder injury), Aiyuk ranks seventh in the NFL in receiving yards per game (88.1), first in yards per target (13.8), air yards per target (14.83) and yards per reception (19.6), second in yards per route run (3.44) and third in receptions going for 20-plus yards (42.2%). Of his 45 receptions, 40 have gone for either a first down or a touchdown