Photo: Jeff Chiu / Associated Press

The discussion of all-time Raiders centers starts with Jim Otto, which made the comparison head coach Jon Gruden drew Wednesday a notable one.

With Otto in Napa last weekend for an alumni event, Gruden said he struck up a conversation with the franchise’s first center about its current one, Rodney Hudson.

“There are a lot of similar qualities,” Gruden said, “in terms of toughness, passion for football and communication. And just all-around effort.”

Doubters of Hudson’s toughness can see Week 15 last season, when he played all 66 offensive snaps in a loss to the Cowboys with a kidney stone. He hardly practiced the next week — then played all 67 snaps against the Eagles, a game for which Gruden was in the broadcasting booth with ESPN.

Hudson was the only player credited with playing 100 percent of the Raiders’ offensive snaps in 2017 — doing so for the second season in a row — and was named to his second consecutive Pro Bowl.

What stands out to Gruden, however, is far less glamorous.

“The thing I love about Hudson is when we throw a pass, he runs down to cover,” Gruden said. “He runs down to see if the receiver needs any help. Every play.”

Take, for example, Week 1 last season against Tennessee. On a screen pass to running back Marshawn Lynch, Hudson released and flattened safety Jonathan Cyprien 5 yards beyond the line of scrimmage. As the play continued, Hudson followed Cyprien and, another 5 yards downfield, pushed him down again on Lynch’s 16-yard gain.

Hudson, 29, said finishing plays is a habit he started at Florida State.

“Anything can happen,” Hudson said. “I mean, trying to get that extra block downfield for a touchdown. Anytime anybody’s around our (running) back, we want to be there. The ball could pop out, anything. So just try to get downfield and make something happen.”

Teammates and coaches have raved in the past about Hudson’s attention to detail and studious nature. That is particularly valuable this offseason as the Raiders are learning Gruden’s complex offense and Hudson is the one reading defenses and calling assignments to fellow linemen.

During Wednesday’s practice, the Raiders spent 10 minutes in a situational drill with the offense working on blitz pickups. Gruden and defensive coordinator Paul Guenther have made clear their intention to outfox the other in practices. This was one of the first live drills of training camp, and Gruden called it “huge … physical.”

“When you’re in the pivot and you’re playing against Guenther, a lot of things change,” Gruden said. “It looks like they’re bringing a blitz to the left and then they’re bringing a blitz to the right or they’re coming up the middle.

“(Hudson) made a couple calls late in the down that were awesome today. It’s fun going to work with the battery that we have. (Quarterback) Derek Carr and Rodney Hudson are showing some really good communication and understanding of our system and what we want to do.”

The Raiders did fairly well protecting Carr last season — 24 sacks allowed tied for third fewest in the league — and Hudson was a big reason. According to Pro Football Focus, Hudson played 592 pass-blocking snaps and allowed three pressures. The one sack he allowed, in Week 17 against the Chargers, was the first Hudson had surrendered in the regular season since 2015.

In June, Hudson said he wanted to learn the Raiders’ new offense from every vantage point — not just the line — because “it helps me play faster.” On Wednesday, he said that process is ongoing.

“I think I’m getting a grasp on it,” Hudson said. “But along with knowing the offense, you have to know the defense, too. I think that’s the part that’s going to take time, is just knowing what they like to do and being able to anticipate and play fast.”

Hudson also was told Gruden had compared him to Otto and asked what he thought Gruden meant by it. The understated center replied: “I don’t know.”

Just in case, Gruden clarified.

“He’s the best center that I’ve coached,” Gruden said.

Matt Kawahara is a San Francisco Chronicle staff writer. Email: mkawahara@sfchronicle.com Twitter: @matthewkawahara