NAPA, Calif. — When the 49ers and Raiders cooked up the idea of a shared training camp, the goal was to raise the intensity level of practice.

As Ricky Brown might attest, the plan worked just fine.
Brown was the unfortunate Raiders linebacker pitted against 49ers running back Frank Gore during a blocking drill Tuesday.
Gore was a 217-pound wrecking ball and treated Brown like a condemned building. He delivered a whopper of a block that finished with Brown’s back planted into the turf.
Raise the intensity level of practice?
Gore treated the action like it was the fourth quarter of the Super Bowl rather than 9:17 a.m. on a fog-softened Napa Valley morning.
“I was amped up,” Gore said. “When you’ve been going against your own guys, you get tired of it.”
The shared practice, the first of a two-day session in Napa, was the brainchild of two coaches no longer employed in the Bay Area. A little more than a year ago, the 49ers’ Mike Nolan and the Raiders’ Lane Kiffin got to talking about the potential benefits of a get-together.
They sketched out a practice schedule, figured out how to choreograph 160 players over two football fields and arranged for football’s Hatfields and McCoys to meet one day last August.
It wasn’t a game or a scrimmage. It was just a super-sized version of the same practices they run every day.
Last year’s event was so smooth and productive that this year the 49ers and Raiders decided to double the itinerary. New coaches Mike Singletary and Tom Cable recently teamed up to plan consecutive days of 8:30 a.m. and 4 p.m. practices.
“Actually, it was done relatively easy, Singletary said. “He talked to his coordinators. I talked to our coordinators and just got a feel for what they needed. We threw out a format that looked pretty easy and then, boom, it was done.”
The locals are not the only NFL teams to explore the benefits of joint practices. In past years, the Chiefs-Vikings, Jets-Giants and Rams-Titans have gone the odd couple route as well.
In this case, the Raiders’ spacious, secluded training-camp facility makes sharing easy. Located behind the Marriott Hotel, two football fields run side by side. (Most of the year, these fields are used for youth soccer leagues and junior high P.E. classes).
On Tuesday, the Raiders opened at 8:33 a.m. by stretching on one field while the 49ers did the same on the other.
The mingling came later. And by mid-morning, mixed action covered almost every inch of turf. Raiders managing general partner Al Davis patrolled the scene from the comfort of a chauffeured golf cart. John Madden, the former Raiders coach, did the same in a separate cart (one that was nowhere near as luxurious as his Madden Cruiser).
Every drill had a competitive element that matched the 49ers against the Raiders. Linebackers vs. running backs. Receivers vs. defensive backs. Offensive linemen vs. defensive linemen.
With so much going on at once, where does Singletary cast his eyes?
“Everywhere,” he said.
The morning session concluded with each 49ers quarterback contender getting a shot at the two-minute drill against the Raiders defense. The Raiders wore white, the 49ers wore red. And the quarterbacks wore yellow jerseys, as if they had just won a stage at the Tour de France.
The yellow is a warning to keep your hands off. Defenders are not allowed to touch the quarterbacks in practice. Other ballcarriers can be hit, but there is no to-the-ground tackling, even in 11-on-11 drills.
In the two-minute drills, both Shaun Hill and Alex Smith got the team to about the same spot.
But Joe Nedney missed a 51-yard field goal on Hill’s drive and missed from 49 after Smith’s drive.
Worse, Nedney’s second attempt sailed over a fence and into an adjacent apartment complex. Apparently even millionaires can lose their ball in the neighbor’s yard.
At 10:40 a.m., a triple-horn blast signaled the end of the morning session. And as weary players trotted off the field, the coaches felt a shared satisfaction regarding the shared practice.
“The competitiveness is there,” Cable said. “You get away from hearing the same calls and seeing the same routes. This gives you a chance to really dial in. This is chance to get better.”