Per Clarence E. Hill Jr. of the Fort Worth Star-Telegram, Witten said the Cowboys roster has "the most talent I've seen" in his time with the organization.
After spending last season in the broadcast booth for Monday Night Football, Witten announced in February he would return to the Cowboys.
"The fire inside of me to compete and play this game is just burning too strong," he said in a statement. "This team has a great group of rising young stars, and I want to help them make a run at a championship. This was completely my decision, and I am very comfortable with it. I'm looking forward to getting back in the dirt."
Dallas certainly has enough talent to be among the best in the NFC in 2019. Its defense ranked sixth in the NFL with 20.3 points allowed per game and seventh with 329.3 yards allowed per game last season.
Quarterback Dak Prescott has had his ups and downs, but the 25-year-old completed 67.7 percent of his attempts in 2018 and has thrown at least 22 touchdown passes in each of his first three seasons.
The Cowboys also have Ezekiel Elliott, who has led the league in rushing yards twice in the past three seasons, and Amari Cooper, who notched 725 receiving yards and six touchdowns in nine games last year after he was acquired from the Oakland Raiders.
Witten has been a steady performer throughout his career with at least 60 receptions in 14 straight seasons from 2004 to 2017. He can be Prescott's safety net in the middle of the field and add another dimension to the offense of the defending NFC East champions.