NAPA, CA -- As you watch Oakland Raiders practice this summer, you feel something different in the air.

You also see it. Quarterback Derek Carr looks very comfortable behind center even though he's only beginning his second season. The Raiders may have hit on a No. 1 wide receiver with the selection of Amari Cooper in the first round; he's made an immediate impression. Michael Crabtree moved across the Bay and is having the best camp of any Raider, looking completely rejuvenated and healthy.

All of a sudden, a franchise that had been a black hole for quarterbacks is starting to look a a little more like the fertile wine fields around this Napa training camp. The Raiders offense might be a year away from coming of age, but it appears to be ready to bolt out of the bottom five places to be for an NFL quarterback.

Since 2003, the Raiders have ranked 21st or worst on offense eight times and 23rd or lower in points scored nine times. Making matters worse is the fact they have finished 20th or higher for points allowed for eight consecutive years. Last year, they ranked 32nd on overall offense and defense for yards allowed, and were outscored by 199 points in what turned out to be a 3-13 season. It's a bad combination when you have a defense that can't stop teams and an offense that can't put up good numbers playing catch-up.

The hope this year is new coach Jack Del Rio can improve the defense while Carr matures with the additions of Cooper, Crabtree and more athletic tight ends. Since OTAs began, Carr has noticed extra energy on the field, thanks to Cooper and Crabtree.

"Oh man, you see the level of competition just rise once they got onto the field," Carr said. "You see when those guys came out how hard the other guys are working because they are competing now. Any time new talent comes in, you are always competing."

Cooper has the look of a true No. 1. He's big, strong, fast and has great hands. Cooper is so talented, the coaches have even looked at him as an option on punt returns. The 49ers thought they drafted a future No. 1 receiver when they made Crabtree the 10th pick in the 2009 draft. Though he had flashes of brilliance, Crabtree produced only one 1,000-yard season in six years in San Francisco. Coming to Oakland, he might have found the perfect spot being in the role of being a No. 2 receiver on the other side of Cooper.

"I think Crab is giving us some of what we brought him here for," Del Rio told reporters Wednesday. "He's friendly to the quarterback and Derek's a good, young player, so that's great competition over there for our defensive backs to work against a good quarterback and a good receiver ... I like the way we're working.''

Asked to be a No. 1 WR in San Francisco, Michael Crabtree could thrive with Amari Cooper around. AP Images/Eric Risberg

Since 2003, 18 different quarterbacks have started for the Raiders. Carr has a unique opportunity this year. If he starts 16 games, he will have 32 starts in his first two seasons. If he survives the season, Carr would be the longest tenured quarterback for starts during the past 13 years.

Carr completed 58.1 percent of his passes last season and had 21 touchdown passes. Expect better things this year.

"I heard Peyton Manning and other guys talk about the rookie year being such great experience," Carr said. "That's what it was for me. It was a great experience to learn how efficient you have to be on every single play. Just having more control of the offense in the second year and just having more confidence coming off a rookie year is important. You've seen it. You know what to expect."

What also helps Carr is that he had experience in a pro-style offense during his early days at Fresno State. It was only his last two years in college he was in a spread offense.

"It's a different game now," Carr said coming from a spread to a pro-style offense. "There is a heightened sense of urgency in the pros. In college, we'd run over 100 plays. You are there, 'First down, ah, I'm just going to take this shot. Why not?' It can't be 'why not' any more. Each play is so critical."

Worst QB situations

After I'd raved some about what I was seeing in practice, I was asked by one of my editors whether the Raiders had graduated from being a bottom-five QB situation. Good question. Here are what I'd consider the current bottom of the barrel in terms of QB situations.

1. Jacksonville Jaguars: The Jags have been 32nd, 29th, 31st and 31st in offensive yards and 28th, 30th, 32nd and 32nd in points scored since 2011. Blaine Gabbert didn't work out as a first-round pick. Chad Henne couldn't fix things either. The hope is Blake Bortles, and his hope is based around wide receivers Marqise Lee and Allen Robinson and tight end Julius Thomas. A decent running attack would really help.

2. Tampa Bay Buccaneers: Jameis Winston has the talent, but does he have the protection? The Buccaneers may start two rookies -- Donovan Smith at left tackle and Ali Marpet at guard -- on the offensive line. Lovie Smith tried to fix the line through free agency last year, but left tackle Anthony Collins didn't work out and was released. Winston is blessed with two quality receivers (Vincent Jackson and Mike Evans) and a good, young tight end (Austin Seferian-Jenkins) so there are plenty of reasons for optimism if the blocking works out at all.

3. Houston Texans: The Arian Foster groin injury dropped what was a decent offense into a troubling one for quarterbacks Brian Hoyer and Ryan Mallett. When Foster starts, the offense averages 23.7 points per game. When he's out, the number drops to 19.4. Further complicating things was the release of wide receiver Andre Johnson, who was aging but still productive. Bill O'Brien's coaching makes this an attractive spot for a quarterback, but the first half of the season will be tough if the running game isn't there.

4. Buffalo Bills: It's not the roster talent, it's the quarterbacks. It's hard to pick between Matt Cassell, E.J. Manuel and Tyrod Taylor, and not in a good way. Each day, no one can guess who will have the better day. The shame of it is the riches available in the passing game. The Bills have a great runner (LeSean McCoy), good receivers (Sammy Watkins and Robert Woods) and a quality tight end (Charles Clay), not to mention the ever-interesting Percy Harvin. The season will be determined on how well the QBs play.

5. New York Jets: Geno Smith isn't fond of ratings that have him considered the 32nd best quarterback in the league. But he has to prove himself this year or the Jets will be looking for his replacement, if that guy isn't already on the roster. Since Mark Sanchez was drafted in 2009, the quarterback's success was dependent on the surrounding cast. Sanchez went to two conference championship games in his first two years, but his performance levels dropped as the talent around him declined. The Jets added Eric Decker and Brandon Marshall over the past two years, but if Smith isn't supported by a good running game, he might remain at No. 32 by the end of the season, and a bad start could make this Ryan Fitzpatrick's team.