BOURBONNAIS — Charles Leno continues to exceed expectations.

The Bears’ 2014 seventh-round pick was pressed into service at left tackle in Week 4 last season for injured nine-year veteran Jermon Bushrod.

Leno played so well that he hung on to the job of protecting quarterback Jay Cutler’s blind side, even after Bushrod, a two-time Pro Bowl player, returned to health a month later.

Now, Leno appears entrenched.

He wound up starting the final 13 games last year and performed at a high enough level that the rebuilding Bears saw no need to address his position in the draft or free agency.

Two veteran free-agent interior offensive linemen have been added to the roster — Ted Larsen and Amini Silatolu — and another free agent, Bobby Massie, was signed to start at right tackle.

Larsen is now the starting center, and second-round pick Cody Whitehair is the starting left guard.

But the Bears were able to stand pat at left tackle, and they love how Leno has handled that critical spot, even if he’s not getting much love from outside his own team.

“Charles Leno is probably the most underrated offensive lineman in football,” said Bears offensive line coach Dave Magazu, a 14th-year NFL assistant. “He comes out every day, works his tail off, and he’s a student of the game.”

Flying under the radar for NFL left tackles usually is a good thing, considering their names are most frequently heard when they allow their quarterbacks to be sacked.

So the 6-foot-3, 305-pound Leno is pretty sure it’s a good thing to be underrated.

“It’s nice, I mean, thanks?” a smiling Leno said when asked

about his reaction to Magazu’s assessment. “What am I supposed to say to that? I like being underrated; that’s the type of person that I am.

“I like to fly under the radar, I don’t like to be talked about all the time, I really don’t. That’s not something for me.

“I like when my teammates talk about me; I like when my coaches give me praise in the meeting rooms. I really don’t care about the outside noise, but if the coach says I was the most underrated that’s kind of cool … I guess.”

Cutler has the most to lose if Leno doesn’t do his job effectively, and he agrees with the O-line coach.Cutler was sacked 29 times in 15 games last season, the second-fewest sacks per start he has endured in seven seasons with the Bears.

“He’s quiet,” Cutler said of Leno. “He’s underrated. But you put on the film, and every single play he’s doing his job. I think everyone’s starting to take notice of what kind of player he is, and he’s going to continue to get better. He’s still a young guy.”

Leno, drafted 246th overall out of Boise State after starting 39 straight games for the Broncos, is just 24. His ideal arm length (34 3/8 inches), agility and athleticism were offset by some technique and strength shortcomings, but he has worked hard to improve in those areas.

Since the Bears’ offensive line already has suffered a season-ending injury to starting center Hroniss Grasu, diminishing what little depth there was, it’s depending on Leno more than ever.

“They know what kind of person I am, and I’m the type of person who goes to work every day,” he said. “I just want to be the best person I can be. They know that’s my work ethic; it comes (from) within me.”

Magazu believes the best is yet to come for Leno, who as a late-round pick under contract through next season is one of the best bargains in the NFL.

“As long as guys listen and they work at it and then they have the skill set, they have a chance to become better,” Magazu said. “He’s going to keep getting better because he’s athletic and he’s smart.

“He has some shortcomings like every guy does, but I don’t think they’re even near the positives.”

As long as coaches and teammates know that, it’s all good with Leno.

• Follow Bob’s Bears reports on Twitter @BobLeGere.