SANTA CLARA -- Safety Antoine Bethea notices the difference before the snap, when he's engaged in a mental game with the quarterback.
The 49ers' nine-year veteran safety likes to look at his opponent's shoulders to see if they're shifted to one side of the field and at his eyes for tips on where the quarterback is going with the ball. Young quarterbacks have a tendency to stare down their receivers, Bethea said. The savvy ones will stare directly at the safety, freezing him in one spot.
After Colin Kaepernick spent the first three months of the offseason tweaking his mechanics and otherwise learning how to become a better passer, observers spent the spring looking for big changes in stance and delivery. Those alterations are there, but they are subtle. Teammates instead have seen differences in other ways.
"Just not telegraphing where he’s going,” Bethea said. “That’s a key thing for a quarterback. He did a great job of that during OTAs. ... That was definitely something that stuck out with me. I could tell he worked on his craft."
Never miss a local story.
The other starting safety, Eric Reid, said he noticed improved touch from Kaepernick, especially on deep balls.
"Everybody knows he has a rocket and can get it into tight windows," Reid said. "But he’s making the touch throws on the deep throws, and the ball is hanging and dropping over the (defensive backs). It’s exciting to see.”
All of which ties in nicely with changes the 49ers are making to their offense this season.
The team added more deep threats to the roster and has a coaching staff that has openly said it is seeking big-chunk plays this season. "Explosion plays – that’s where you make a living,” quarterbacks coach Steve Logan said earlier this year.
Those types of gains were conspicuously absent last season.
The 49ers' best down-field threat, tight end Vernon Davis, had the worst season of his career with only two catches of 20 yards or more and none beyond 30 yards. The team's top three wide receivers -- Anquan Boldin, Michael Crabtree and Stevie Johnson -- were adept at short- and mid-range routes but weren't speedy, big-gain threats.
Meanwhile, Kaepernick’s yards-per-pass-attempts average, which was a league-high 8.3 yards after he took over as starter in 2012, dropped to 7 yards last year, one of the lowest among NFL starters. His touchdown-to-interception worsened from 21-8 in 2013 to 19-10 last season.
During the offseason, the 49ers added wideouts Torrey Smith and Jerome Simpson in the hope of creating a deep attack that will work in concert with a robust running game. Smith, who signed a five-year, $40 million contract, is the team's most expensive free-agent acquisition since general manager Trent Baalke was named to his post in 2011.
The harmony between Kaepernick and Smith is critical to making the new strategy work. And as Reid noted, the connection began to click in the spring.
Smith, who spent his first four seasons in Baltimore, said he's trained alongside Kaepernick during previous offseasons and was familiar with the quarterback's work ethic. But he said it's even more impressive to see at 49ers headquarters.
"There's no one that works harder than Kap. I'll say that to anyone," Smith said. "He wants to be great. He's putting the work in, and it's on us to make sure that it all works out."
Kaepernick also will be asked to deliver the ball with touch on short passes. Reggie Bush, who has more career catches than any active running back, is expected to have a role as a third-down pass catcher. The plan is to make defenses pay for blitzes and aggressive up-field pass rushing by flipping screens to Bush out of the backfield.
How is the chemistry between Bush and his quarterback so far?
“I think we're right on track,” Bush said. “Thinking back to OTAs and minicamp, I think we really hit it off.”