He met with team officials, including coach Kliff Kingsbury, on multiple occasions leading up to the 2019 NFL Draft and thought there was a slim chance he would be the No. 1 overall pick.
Bosa figured quarterback Kyler Murray was the likely No. 1 selection for Arizona. But he was not sure until he heard Murray's family erupt in cheers in the green room at the draft in Nashville when the Cardinals made it official.
The 49ers selected Bosa with the No. 2 overall pick. He is having a fine rookie season for the 49ers with seven sacks for a club that has the NFC's best record at 9-1.
Meanwhile, the Cardinals fell to 3-7-1 with a 36-26 loss to the 49ers on Sunday at Levi's Stadium.
Still, Bosa said it is obvious to him Arizona is moving in the right direction with the right person at quarterback. The Cardinals were 3-13 last season and were granted the No. 1 pick as the NFL's worst team.
"I'm impressed with how they've turned things around over there," Bosa said of the Cardinals. "In the draft process, they sold me. I definitely saw the vision they had and how they were going to do it. I think they're doing a really good job.
"And Kyler is a really good player, so they picked a good one."
Bosa had Murray's grass-stained jersey hanging in his locker after the game, as the top two picks in the draft met afterward to exchange uniforms.
Bosa registered three tackles, including one for a loss, and a quarterback hit on Sunday. In two games against the Cardinals, Bosa did not record a sack. Arizona's offense exposed some issues in the 49ers' run defense. Murray ran for 67 yards on eight attempts in Sunday's game.
The 49ers came up with the plays necessary on offense and defense to avoid back-to-back losses after opening the season on an eight-game win streak.
"I definitely think that was a big must-win for us, a division game," Bosa said. "(We) just came off a loss, you don't want to drop two in a row, that's for sure."
The Cardinals appear to be a team on the rise, and the 49ers enter the final six games of this season with a one-game lead in the NFC West over the Seattle Seahawks. The stage could be set for a lot more epic 49ers-Cardinals games in the future with Bosa and Murray leading their respective units.
"The running game, we just have to figure out how to stop that," Bosa said. "But we'll wait ‘til next year for that."
Why 49ers' Nick Bosa believes Cardinals made right call with Kyler Murray originally appeared on NBC Sports Bay Area