The Broncos have opened contract extension negotiations with cornerback Chris Harris, according to NFL sources.

One of the team’s most pleasant surprises since the Broncos signed him to a mere $2,000 bonus as an undrafted rookie out of Kansas in 2011, Harris is eligible for unrestricted free agency after this season.

“My focus is on the team and trying to help this team win a Super Bowl,” Harris said.

It hasn’t always been easy for the Broncos to get a new deal done with one of their own. They had contract negotiations with wide receiver Demaryius Thomas and tight end Julius Thomas before training camp in July, but those talks stalled in August.

What kind of contract would it take for the Broncos to secure Harris for the long term? Based on how he’s been graded by Pro Football Focus, Harris doesn’t have to be shy about his asking price. Entering the Broncos’ Week 10 game Sunday at Oakland, Harris has the third-best overall rating among NFL cornerbacks, behind the Indianapolis Colts’ Vontae Davis and San Diego’s Brandon Flowers.

Harris, 25, also has the top coverage grade among cornerbacks. But the website’s rankings don’t differentiate between No. 1, No. 2 and nickel backs, as each NFL team does. During his four seasons with the Broncos, Harris has been a nickel back or a No. 2-outside cornerback, where he played opposite Champ Bailey, Dominique Rodgers-Cromartie or Aqib Talib.

Arguably the league’s best No. 2 corner, Harris, is making $2.187 million this year after he received a second-round tender as a restricted free agent.

Now that he’s proven to be fully recovered from a partially torn ACL injury suffered during a January playoff game against San Diego, Harris is in position to command a substantial raise.

This past offseason, Green Bay gave Sam Shields a four-year, $39 million contract extension ($9.75 million per season) and the Colts re-signed Davis to a four-year, $36 million deal ($9 million average). Free agents Brent Grimes signed with Miami for four years and $32 million ($8 million) and Rodgers-Cromartie left the Broncos for the New York Giants and a five-year, $35 million deal ($7 million average).

As with any NFL multiyear contract, guaranteed money and structure of years one, two and three accompany total dollars as the three key components.

In many ways, Harris is a model Bronco. A four-year starter at Kansas, Harris went undrafted in part because he was shifted from corner to safety as a senior, and he doesn’t have a blazing 40 time.

But he was discovered by the Broncos’ scouting system during the lockout of 2011 and John Fox’s coaching staff realized in his first training camp that Harris is a fierce competitor who finds a way to stick with any receiver.

A nickel back through his first 2½ seasons, Harris moved to an outside corner position midway through the 2013 season. When he suffered his partially torn ACL on a noncontact play in the third quarter of the Broncos’ second-round AFC playoff game Jan. 12, San Diego quarterback Philip Rivers rallied the Chargers back in the game by picking on Harris’ replacement, Quintin Jammer.

Harris underwent surgery, missed the rest of the 2013 season, including the Super Bowl, and the entire 2014 preseason, but he has been superb through the first half of the regular season.

Besides his two interceptions, Harris ranks third in the league in pass deflections (11) and opponent quarterback rating (41.4).

Negotiations for a new, more lucrative contract are coming along at a good time. Harris’ wife, Leah, gave birth two weeks ago to their daughter, Aria.