SANTA CLARA – The 49ers just blew another 10-point lead in the fourth quarter and lost 24-23 to the Arizona Cardinals. Now the 49ers are 2-3. Here are her grades for this pathetic performance.

QUARTERBACK: D

Brock Purdy is a great scrambler – today he averaged 8.3 yards per carry. But as a passer, when he doesn't have Christian McCaffrey, he's a glorified Jimmy Garoppolo. Call him Purdy G. In his last 10 starts, he has thrown 11 touchdown passes and nine interceptions and his record is 5-5. The essence of mediocrity. Apparently he's not that great without the Offensive Player of the Year in the backfield. This season he regularly holds the ball too long and tries to make big plays when he doesn't need to. In the last two weeks, he threw two second-half interceptions while leading by several points. This means that he lets the opponents back into the games. The 49ers would be wise to take the game out of his hands and take the ball with a lead in the second half. He's not the franchise quarterback they thought he was. Good thing they found out before he was eligible for a contract extension.

RUNNING BACKS: B-MINUS.

Jordan Mason gained 89 yards on 14 carries, but failed for the second straight game and this time the opposing team recovered, meaning he is one of the main reasons for the 49ers' defeat. He's still a great ball carrier, but he'll be benched if he continues to put the ball on the floor. Luckily for him, he's still much better than his backup, Isaac Guerendo, who has terrible vision for a running back.

Full-back: F.

No goals. No catches. No wearing. No touchdowns. Lots of cardio though. Nobody runs as well as this guy, which is why the 49ers are paying him more than $4.5 million per season. To run around and have fun.

WIDE RECEIVER: C

Jauan Jennings had just one catch for 13 yards despite being open in the end zone and throwing behind Purdy. Jennings needs more opportunities. Brandon Aiyuk finally lived up to his contract – he had 8 catches for 147 yards. Maybe he just needed a month to get into football shape after sitting out the entire training camp. Or maybe he just had to play against the Cardinals. Hard to say. Deebo Samuel didn't benefit from the game against Arizona – he only had 20 yards to go. Good thing this season will most likely be his last with the 49ers. He seems old.

TIGHT ENDS: A-MINUS.

George Kittle dropped one pass but also caught 8 for 64 yards and a touchdown. He is their entire offensive player in the red zone.

OFFENSIVE LINEMEN: A

Admittedly, they played the worst front 7 in football. But they paved the way for 5.9 yards per carry and gave up just two sacks, and neither sack was their fault. Purdy came under pressure on his own throughout the game.

DEFENSIVE LINEMEN: B-MINUS.

There was a big interception on Nick Bosa, but overall this group couldn't contain Kyler Murray – what else is new? They gave up a 50-yard touchdown run and sacked him only once. And they couldn't stop James Connor in the second half either. They are thin and just worn out. That doesn't bode well for Thursday night in Seattle.

LINEBACKER: C-MINUS.

Fred Warner recorded a whopping 12 tackles, but De'Vondre Campbell left that 50-yard touchdown run to Murray. Campbell is old and slow. The 49ers can't bench him fast enough.

DEFENSIVE BACKS: B-MINUS.

They posted a passer rating of just 79.2, but they also allowed a 14-yard catch on 4th-and-5 with the game on the line. Notably, Isaac Yiadom gave up this catch to Marvin Harrison Jr. Yiadom is a burden.

SPECIAL TEAMS: A-MINUS.

The 49ers blocked a field goal and returned it for a touchdown – that should have been the difference in the game. Unfortunately for the 49ers, Jake Moody suffered a sprained ankle while attempting a tackle and the 49ers were forced to play the second half without a kicker.

Coach: F.

Nick Sorensen had a good plan to shut down James Connor, and the 49ers executed it in the first half. But then the Cardinals made adjustments in the second half and Sorensen didn't and the 49ers lost. Nick Bosa said afterwards that the lack of adjustments was a big reason for the defeat. Bosa also said the lack of complementary football on offense weakened the team. That is, they passed when they should have, while leading by several points in the second half. This is how Kyle Shanahan always blows a 10-point lead in the fourth quarter. He stops running the ball. He cares more about having an explosive offense than actually winning. And that's why he's a fraud. Since 2017, when he was the Falcons' offensive coordinator, he has blown fourth-quarter leads. His specialty, his purpose, is to grow leads in the fourth quarter. It's time to replace this choking artist before he gives away another win to an inferior team. No coach does less with more than Shanahan. That is his legacy. Get him out of here.