Brock Purdy puts on a show against the Cardinals (and Tom Brady agrees)

On this sweltering day in Santa Clara, California, the San Francisco 49ers lead the Arizona Cardinals 23-10 at halftime.

In a game that featured future Hall of Famer Tom Brady calling his first 49ers game from the booth for Fox Sports, there were already some big plays in the first half.

Cardinals quarterback Kyler Murray ran for a 50-yard touchdown, and the Niners' special teams came up big with a blocked field goal that was returned for a touchdown. 49ers defensive end Nick Bosa also intercepted, putting the offense in excellent field position just before the end of the half.

A big part of the 49ers' lead after the first half is thanks to the play of their quarterback, Brock Purdy. He was great in the first half of this game, throwing for 165 yards and a touchdown without turning the ball over.

Purdy faced wide receiver Brandon Aiyuk repeatedly in the first half. After four games in which Aiyuk averaged 41.8 yards per game, he now has six carries for 115 yards in the half. This is his first 100-yard first half in his career

When Brady was asked his opinion of Purdy, the first word he said was “impressed.” He then described Purdy's maturity as a leader of this 49ers team.

“What strikes me about him is just his maturity,” Brady said of Purdy. “For me it's about how you can process a lot of information in a short time. Can you be a great leader and be reliable for the organization? He is all of that.”

In a game where kicker Jake Moody left the game after suffering an injury on the kickoff, the 49ers will have to rely heavily on Purdy in the second half.