SANTA CLARA -- Tight end Vernon Davis knows what a difference a year makes at the 49ers' quarterback spot.
Gone is Alex Smith, his training-camp roommate and longtime pass distributor.
This camp, Davis has his own room and a blossoming rapport with quarterback Colin Kaepernick.
Those two quarterback worlds collide Friday night when the 49ers play an exhibition game against the host Kansas City Chiefs, to whom the 49ers traded Smith in March.
Once a big-time advocate on Smith's behalf, Davis is connecting better each day with Kaepernick, such as on a 30-yard pass that opened Monday's team drills.
"Last year when he first got the starting job, we'd be at practice and he'd keep overthrowing me," Davis said of Kaepernick. "I'd be running as fast as I possibly could, and Colin just kept overthrowing me.
"Now we get out there and it's night and day. He puts the ball right there. Man, he's come a long way."
Last summer, Davis didn't envision thriving with Kaepernick, merely because Smith was the starter. Smith's Nov. 11 concussion changed that, as he lost his job to Kaepernick.
"I thought Alex would always be here," Davis said.
Smith got dealt to Kansas City in March for two draft picks -- a 2013 second-round choice and a 2014 conditional pick. That ended Smith's eight-season tenure, the final two of which saw him blossom under coach Jim Harbaugh.
"It's personal with Alex," Harbaugh said of Friday's reunion. "(I) feel like there's a great friendship there and a lot of history. He's a unique person, a good friend.
"But he's no longer on our team. Not a trusted agent anymore."
Smith agreed this game will be "definitely different" because of the opponent.
"These are a lot of my good friends," Smith said on SiriusXM NFL Radio. "But the weird thing is that it is a still a preseason game. If it were a regular-season game, we'd have a little more to talk about."
Davis said he hasn't kept in touch with Smith because: "I want to stand back and let him do his own thing. And I've got enough to do here."