Brock Purdy has faced and passed a number of tests since taking over for Jimmy Garoppolo.
The one he got from the Las Vegas Raiders was the most difficult.
It was the first time that the Niners faced a fourth-quarter deficit and nobody knew how they'd handle it. As has been the case with all the other tests, Purdy earned more high marks as the 49ers beat the Raiders.
San Francisco's nine-game winning streak is its longest since 1997.
Since 2004, only Ben Roethlisberger has won four straight starts for a rookies. His coach and many of his teammates are ready to say that this is more than a flash in the pan after he did it in a game in which the Niners got their second win when trailing by double digits.
"What Brock's doing is not fake," he stated. When he makes mistakes, he understands why and tries to learn from them. He doesn't have a lot of experience. When he plays the game the right way, he's only going to get better from it. I think that the fact that he didn't get in his other four games helps.
The quarterback was 22-of-35 with two touchdown and an error for a 68.6 QBR. It was his fifth game in a row with at least two touchdown passes, tying for the second-longest streak by a rookies since the 1970 merger. In the past five games, Purdy has thrown at least one touchdown in each game, tying the record for most touchdown tosses by a rookies in a single game.
In the fourth quarter, he was able to do a lot. He had played a total of nine snaps with the 49ers trailing at any point in the five games he has been the starter. He entered for Garoppolo with 9:30 left in the first quarter of the Dolphins game.
Purdy was unperturbed by the score.
"I feel like he's kind of sped me up a little bit because he's the type of player that's calm, he's good, and he plays this game at the quarterback position, so I feel like he's the type of guy that's good I think this dude is on a different level and he can play for sure, that's what I saw today.
Four Niners scoring drives in regulation led to the victory. He was 6-of-10 passing for 113 yards with one drive ending in Jordan Mason's rushing touchdown and another missing a field goal.
He said that he hadn't played in a close-and-late situation since his time at Iowa State, and that he was thankful for the help of his teammates. He was happy to finally face some game pressure.
Purdy said that he doesn't have to feel like the weight of the world is on his shoulders. I have to do my job. It was great to have a game like that where the game is on the line and we have to score. I felt it again after going through that.
The 49ers leapfrogged the Vikings for the second seed in the playoffs. The Niners have a better record in the playoffs than the other team. If the Minnesota Vikings lose to the Chicago Bears next Sunday, the San Francisco 49ers will finish second.
If the Philadelphia Eagles lose to the New York Giants in Week 18 then the San Francisco 49ers have a chance at the No. 1 seed and home field advantage throughout the playoffs.
"I think it's important." We want to get into the playoffs. The tournament is where you have a chance for the ultimate goal. Once you get there, you have to position yourself the best way you can, and we don't know until we get there, but they tell us if we can take care of business, and that's what we need to do. Our playoffs began a long time ago and we are going to keep going.