Pull up a chair at any local watering hole, or even one in your house for an online chat, and say you think Derek Carr is better than Colin Kaepernick. Or that Kaepernick is your choice.

Pack a lunch … and some snacks, because you might be going back and forth for a while.

The problem is that it’s hard to quantify Carr’s potential. The Raiders’ quarterback was solid last year, his rookie season, but he also was playing to avoid interceptions and sacks on a team that started 0-10.

He has all the tools required of a potential franchise quarterback, and the hope (OK, “belief” if you work or cheer for the Oakland team) is that a new offensive coordinator and two shiny new receivers will help Carr realize his potential.

“What immediately stood out about Derek Carr was his arm strength,” ESPN analyst and former Eagles quarterback Ron Jaworski said. “Carr is a very easy thrower with a compact delivery. He does not work hard to drive the football down the field.”

Of course, Jaworski was effusive in his praise of Kaepernick at a similar point in the 49ers’ quarterback’s career, saying in August 2013: “I truly believe Colin Kaepernick could be one of the greatest quarterbacks ever. I love his skill set. I think the sky’s the limit.”

But here’s the thing about Carr: While becoming the seventh rookie to throw for at least 3,000 yards and 20 touchdowns in a season, he also averaged an NFL-low 5.5 yards per attempt. That’s the seventh-lowest season average in NFL history, with names like Joey Harrington and Blaine Gabbert and Chris Weinke just ahead of him.

Carr, perhaps the most upbeat guy one will ever meet, swears that he is his harshest critic. He has watched all the game video from last season, has filled 30 notebooks, and he worked hard in the offseason to take the next step.

“If I don’t get better at everything, I’m going to be mad at myself,” Carr said. “Just to be more efficient. To not take any plays for granted. Not saying that I did, but just really focusing that each play is so important, especially in the NFL.

“I started to learn how close the games were. I don’t know how many games we lost within eight or nine points (five), but it was crazy. … When you’re a rookie, things are flying a little bit faster. Now, it’s nice to just play football. The game slows down, you know what to expect and all of that.”

Third-year receiver Brice Butler has noticed a big change in Carr this year.

“He is more confident,” Butler said. “He has come in this year and (exhales). He told me, ‘I am not worried about anything, I’m just playing football.’ He knows what the next day brings, and this is his team to run.

“He is very comfortable.”

Carr and new offensive coordinator Bill Musgrave hope Carr gets cozier in the pocket. While he avoided taking sacks — his 3.85 percent sack rate was sixth-lowest for a rookie since 1970 — he completed just 42.6 percent of his passes and had a passer rating of 57.0 when pressured.

At Fresno State, Carr admittedly let it rip a little more.

“In college, I can just say, ‘You know what? I’m just going to throw this one up to Davante (Adams) on this play. He’s got man coverage, I’m just going to throw it up. We’ll go for it on fourth down and get it.’

“The mind-set in the NFL, each play has to be so precise, so thought out. You can’t just say, ‘Oh, I’m just going to throw this one up to him.’ Those are the things that I learned after last year.”

Carr completed only 41.8 percent of his passes more than 10 yards downfield last season, and that dropped to 21.1 percent of throws past 20 yards — which ranked 31st out of 36 quarterbacks with 20 or more such attempts.

But those numbers should improve this season with the additions of former 49er Michael Crabtree and first-round pick Amari Cooper. (Last year’s leader in receptions, James Jones, was cut in the offseason.)

“Teams have to decide what corner — who they want to put on who,” Carr said. “They’ve got to decide, because in my eyes, they are both No. 1 receivers. So they have to decide, where do they want to roll the coverage? And both of them can win versus one-on-one, so it makes it hard.

“I think having Crab there alongside Coop has been just awesome for not just one or the other, but for both of them in that sense.”

Carr could even fake it to one of them, and throw to the other … deep.

“I could do little things that I didn’t even think about last year,” Carr said. “Pump one way and then go to another, because I know it will affect the secondary, or little things like that. The game has slowed down to where I can manipulate defenders and things like that.”

Vic Tafur is a San Francisco Chronicle staff writer. E-mail: vtafur@sfchronicle.com Twitter: @VicTafur