In retrospect, the 49ers should have drafted a certain SEC quarterback with the No. 133 pick in 2016, but they can take some solace in this: The SEC cornerback they took instead can play a little, too.
Rashard Robinson may not make anyone forget about the decision to pass on Mississippi State’s Dak Prescott, the No. 135 pick who was the Offensive Rookie of the Year with the Cowboys. But he could make the memory of that move at least a bit less painful.
As a rookie, Robinson, 21, showcased the talent that was evident at LSU, but none of the poor decision-making. Robinson had early-round ability, but he fell to the fourth round because he was kicked off the team after a college career that included one full season and two suspensions.
Viewed as an unfocused character risk, Robinson has been consistently hailed for his feistiness, desire and competitiveness in the NFL.
“He’s a dog — I like him,” defensive coordinator Robert Saleh said. “He’s made of the right stuff. His attitude (and) his mindset is unique for a corner.”
Saleh and secondary coach Jeff Hafley spoke with reporters Wednesday shortly after a practice in which Robinson broke up a pass intended for wide receiver Pierre Garcon and then began jawing at the 10-year veteran. It’s not known if Garcon enjoyed the banter, but Robinson’s fire in the middle of the offseason is appreciated by the staff.
“It’s the same attitude,” said Hafley, in his second season with the 49ers. “It’s the same mindset. It’s the same Rashard.”
Said Saleh: “Every rep is so important to him. He doesn’t care who he’s going against. It’s a tremendous mindset when you get a guy like Rashard who is so focused.”
Last year, Robinson, who had last played in a game in October 2014, started six games and collected eight pass breakups and the game-sealing interception in a Week 16 win at Los Angeles that snapped a 13-game losing streak.
This year, he appears to the only slam-dunk starter in a reshuffled cornerback corps that’s without last year’s starters. Tramaine Brock was released in April after he was arrested for felony domestic violence, and Jimmie Ward has been moved to free safety.
Robinson has started during offseason practices open to the media, while Dontae Johnson and Keith Reaser have shared first-string snaps on the other side. K’Waun Williams and Will Redmond are expected to compete for the nickel corner role.
Robinson, who will turn 22 in July, is suddenly something of a graybeard. Of the 10 cornerbacks on the roster, four have never played an NFL snap and Robinson, Johnson (six starts) and Williams (10) are the only players to have made a start.
Robinson referred to himself as “the older guy” in his position group.
“I’m more mature,” he said. “I’ve got more knowledge of the game. So I’m ready to go.”
Robinson, who is listed at 6-foot-1 and 177 pounds, said he’s nearing 190. And added bulk could help him with his specialty: physical man-to-man coverage. Under Saleh, the 49ers have switched to a 4-3 defense, but their need to have corners who can stay on a so-called island and jam wideouts near the line of scrimmage hasn’t changed.
In addition to playing the same style, this figures to remain unaltered as Robinson enters his second season: He’ll keep barking.
“That’s one thing … just being a dog on the field,” Robinson said. “I’m trying to bring that energy to the defense and to the team.”
Eric Branch is a San Francisco Chronicle staff writer. Email: ebranch@sfchronicle.com Twitter: @Eric_Branch