FOXBORO — To help explain how he’s developed heading into his second NFL season, Patriots left tackle Will Campbell turned to a baseball analogy Sunday.

Campbell confirmed he’s worked on diversifying his sets in pass protection, meaning his starting technique when he’s blocking edge rushers in 1-on-1 situations. Campbell likened it to a pitcher in baseball only throwing one pitch, which would become predictable and give the batter an advantage. Now, Campbell is trying to vary his footwork, hand usage and how much ground he covers going backward — or forward — when protecting Drake Maye.

“Trying to keep people on their toes,” he said. “You know, it’s a chess match between a tackle and an edge rusher. They have a plan, we have a plan, and it’s (about) who can disturb the other one’s plan. That’s just something I’m trying to do, still trying to work on, and I’ve still got a long way to go to be where I want to be.”

Campbell has started every practice at left tackle this summer, save for one he missed due to an apparent left arm injury that led him to wear a large brace. Campbell did not wear the brace at Sunday’s walkthrough and said he wore it earlier this week as a precaution.

As a rookie, Campbell started every Patriots game when healthy last season. He tore his right MCL on Nov. 23, then returned to action late in the regular season and struggled mightily throughout the playoffs. In February, executive vice president of player personnel Eliot Wolf ascribed Campbell’s struggles to the injury and a higher level of competition.

“When he came back from that injury, I personally didn’t see the same level of lower body strength that you saw before the injury. I think the film would attest to that,” Wolf said at the scouting combine. “He probably had three of his four worst games in the playoffs. Before that, I thought Will played really well all year.”