Colin Kaepernick was benched after three quarters on Sunday.
He completed 1-of-5 passes for four yards.
"To me, what's most fascinating about that is what Chip's approach was," Greg Cosell said on KNBR 680 on Monday evening. "Chip (Kelly) clearly did not want him to throw the ball ... it was clear to me that Kaepernick does not throw a wet or a cold ball very well...
"He has small hands so I'm wondering if he just couldn't really throw the ball effectively in this kind of weather.
"Hey, Troy Aikman always said, 'I couldn't throw a wet ball.'"
Kaepernick was sacked five times for -25 total yards.
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"Looking at the sacks, there were opportunities for tighter window, but NFL throws -- and first of all, I don't think Kaepernick is that guy under normal circumstances -- and my sense is, he didn't feel comfortable in this weather," Cosell added. "He certainly wasn't gonna cut it loose on those kinds of throws in this weather.
"Maybe Chip knew that, maybe he didn't. But to me, as I said, it's more fascinating that he didn't have him throw the ball at all."
Blaine Gabbert supplanted Kaepernick and completed 4-of-10 passes for 35 yards. He was sacked once.
