HOUSTON -- The Texans have engaged in "very preliminary" discussions with quarterback Deshaun Watson about a potential contract extension, a source told ESPN's Ed Werder.

On Friday, Houston finalized a three-year, $66 million contract extension with left tackle Laremy Tunsil, a source confirmed to ESPN. With that negotiation complete, Watson becomes the next priority as the team hopes to reach an agreement before the start of the season, a source told Werder.

Watson is one of three quarterbacks who could break the NFL contract record this offseason; the group also includes Super Bowl MVP Patrick Mahomes and Cowboys quarterback Dak Prescott. Dallas has used the exclusive franchise tag on Prescott, but the two sides could still reach a new deal before the start of the 2020 season.

Watson and Mahomes, first-round picks in 2017, are eligible for new contracts for the first time this offseason.

To set a record for a new deal, Mahomes or Watson would have to top Seattle Seahawks quarterback Russell Wilson, who signed a four-year, $140 million contract in April. Los Angeles Rams quarterback Jared Goff, picked No. 1 overall in 2016, has the record for guaranteed money: $110 million included in the four-year, $134 million extension he signed in September.

Watson made less than $3.8 million in 2019, which was just 4.88% of the Texans' cap. He is scheduled to make $4.4 million during the 2020 season.

In 38 games over his first three NFL seasons (his rookie year was cut short by a torn ACL), Watson threw for 9,716 yards, 71 touchdowns and 29 interceptions. He has also run for 14 touchdowns.

At his end-of-season news conference in January, Texans head coach and general manager Bill O'Brien said of Watson, "We want him to be a Houston Texan for his career."

"He is a great person, he's a great football player and he means a lot to this organization, to this city, to this league," O'Brien said. "I just don't want to get into the nuts and bolts of when you would do that and all those different things. Those things take time, but we want him here for a long time."