HOUSTON -- The Houston Texans have agreed to a four-year, $160 million contract extension with quarterback Deshaun Watson, his agent David Mulugheta told ESPN's Adam Schefter on Saturday.

The total value of the deal, to be signed later Saturday, is $177.54 million with nearly $111 million in guarantees, trailing only quarterback Patrick Mahomes' 12-year deal with the Kansas City Chiefs as the largest in NFL history.

Watson will make $39 million per year in base salary, on average, over the next four years, making him the highest-paid player in the NFL during that time frame.

This is the first offseason Watson was eligible to sign a contract extension. Coach and general manager Bill O'Brien said during the offseason that the Texans and Watson's representatives were working on an extension and that "we obviously want Deshaun Watson here for a long, long time."

"I love the guy," O'Brien said of Watson this offseason. "He's an excellent football player, but he's an even better person. He cares about his teammates, he cares about being as good of a player and a teammate as he can be every single day, he tries to get better every day. He's a very smart player. He's gotten better and better, he's improved every single year, and we obviously feel very good about and very fortunate to have him on our football team. I think having that position, as we all know, is very important, and we feel like we have an excellent player there."

In his first three seasons, Watson has played in 38 regular-season games, completing 66.8% of his passes for 9,716 yards, 71 touchdowns and 29 interceptions. He is one of just 11 players to throw for 70 or more touchdowns in his first three seasons, according to ESPN Stats & Information research.

Watson's ability to scramble has also set him apart from other quarterbacks. According to ESPN Stats & Information, he is one of two players in NFL history with multiple seasons (2018, '19) with 25 passing touchdowns and five rushing touchdowns. Steve Young did the same in 1994 and 1998.

The Texans traded up to the No. 12 pick to draft Watson in 2017. He got off to a hot start his rookie year after replacing Tom Savage at halftime of the season opener. In the seven games before he tore his ACL, Watson threw 19 touchdown passes, 16 of which came in his final four games.

Although he has played only three seasons, Watson's 71 touchdowns rank second in franchise history, and his 9,716 passing yards rank third, behind Matt Schaub (23,221 in 90 games) and David Carr (13,391 in 76 games).

Watson enters his fourth NFL season without All-Pro wide receiver DeAndre Hopkins, who was traded to the Arizona Cardinals in March. The Texans have added wide receivers Brandin Cooks and Randall Cobb to go along with Will Fuller V and Kenny Stills.