ENGLEWOOD, Colo. -- On his trek from being a guy some folks in the league said was too short and then going undrafted, to one of the most important players on the field and in the locker room for the Denver Broncos, cornerback Chris Harris Jr. has always been about jumping life’s hurdles to get where he hopes to go.

So, it really is no surprise, as he heals from surgery to repair his left ACL, he plans on being on the field before this summer’s training camp is over and in the lineup when the Broncos open the regular season Sept. 7 against the Indianapolis Colts.

"I haven't had an offseason, I've been here," Denver Broncos cornerback Chris Harris Jr. said on his return since ACL surgery. Kirby Lee/USA TODAY Sports

"I’m ready, I’ve been working my ass off, excuse my language," Harris Jr. said with a smile. “I haven’t had an offseason, I’ve been here. I went to Dr. Andrews [for surgery], that was my little vacation and I’ve been here. Treatment every day and now I’m pretty much doing two-a-days, I’m here at 6:45, then coming back for the meetings and the lift. I’m feeling great, I'll be ready. I’m building my confidence because I wasn’t down too long. I’m able to test things, I just feel confident about what’s going to happen.’’

“I’m not doing everything until mid-training camp,’’ Harris Jr. continued. “I’ll probably be ready at the beginning of training camp, but I probably won’t do anything until mid-training camp. I’ll continue to do my workouts, watch and coach them up.’’

With Champ Bailey’s release, Harris Jr. is now one of the elder statesmen in the Broncos’ secondary, at least when it comes to the team’s playbook. As he enters his fourth season, he has gone from an undrafted rookie who caught Bailey’s eye in 2011’s training camp -- “that kid competes on every play, doesn’t get rattled,’’ Bailey said then -- to a key part in how the Broncos’ go about things on the field.

So much so, that the Broncos allowed a Total QBR of 43.6 in the 2013 regular season when Harris was on the field, according to ESPN Stats & Info. And in the 81 snaps that he wasn't on the field, opponents had a Total QBR of 93.

Ask defensive coordinator Jack Del Rio about Harris Jr. and the word “competes’’ will often be somewhere in the first sentence, as in “he just competes on every play, in practice, in games, he leaves nothing for granted.’’

He's just the do-it-all guy, who can line up outside against an opponent’s best receiver or move down inside to the slot and win those physical battles in the everything-happens-fast area of the of the field. And it was noticeable when Harris left the Broncos’ divisional round win over the San Diego Chargers in the third quarter this past January as the Broncos had a 17-0 lead when Harris Jr. was in the game and the Chargers scored 17 points in the fourth quarter when he was not.

It was a non-contact play, but an injury Harris Jr. believed was coming even before it happened.

“I was definitely surprised, at least a little bit, that it was a partially torn ACL.’’ Harris Jr. said. “But I wasn’t surprised there was something wrong because I had been having little nagging injuries in my left leg for about two years, then after the (Dec. 1) Chiefs game, I couldn’t walk after that game, I was just so sore. I just figured something in my left leg was just wearing down. After a while, that’s why it happened so easy, it was non-contact, I do those same movements every day. So, it was something that was bound to happen, because I just feeling those little pains before. I was probably playing with it before I really knew.’’

Harris Jr.’s scheduled return would certainly help a re-vamped Broncos’ secondary. The Broncos opened owner Pat Bowlen’s checkbook to sign cornerback Aqib Talib and safety T.J. Ward in free agency and then used a first-round pick earlier this month on cornerback Bradley Roby.

Talib and Harris Jr. started together on a Kansas defense that helped the team win an Orange Bowl -- “so we already have that chemistry together,’’ Harris Jr. said -- and thought the Broncos are still in the shorts-and-T-shirts phase of the offseason workouts, Ward continues to draw raves from teammates and coaches alike.

The Broncos hope the plan makes it from the drawing board to the field. Talib and Harris Jr. could be the starters with Roby and Kayvon Webster, a 2013 draft pick, fitting into the specialty packages. If that comes to fruition it would give them a three-cornerback look in the nickel (five defensive backs) and a four-cornerback look in the dime (six defensive backs) that would feature more speed and athleticism than they had last season to match up with three- and four-wide receiver sets.

“Two years ago we finished in the top of the league and last year, we didn’t,’’ Del Rio said. “We like being at the top. So we’ll work our way back. We’ve got good players, good design. We’re going to work hard. And we expect to be good.’’

“This is my third year with Jack now, I feel like I know the defense inside and out,’’ Harris Jr. said. “And we’ve got a lot of new guys, so I try to make it easier on them. But I’m on track to get back out there. I’ve got big plans, so much motivation for this year. This a good team, we expect great things. I'm going to be a part of it, that's for sure, I'm going to be part of it.’’