FRISCO, Texas -- Since April, the Dallas Cowboys have signed defensive end DeMarcus Lawrence, linebacker Jaylon Smith, right tackle La'el Collins and running back Ezekiel Elliott to deals totaling $185.5 million in guaranteed money, which is more than what Jerry Jones paid to buy the franchise in 1989.

The team hopes to deliver more guaranteed money on long-term deals with quarterback Dak Prescott and wide receiver Amari Cooper -- and they hope it can happen before Sunday's season opener against the New York Giants, while acknowledging it might be difficult.

"Don't ever say never," executive vice president Stephen Jones said. "The season doesn't start until Sunday. We still got three or four days here. Obviously we've ended up signing a few players we didn't necessarily know we were going to sign, but at the same time, I certainly felt optimistic that we can get these guys. Whether it's by the start of the season or if it goes over that, it does. That was our goal. Sometimes you don't get it quite done on the exact timing that you had hoped, but obviously the ultimate goal is to get them signed."

The Cowboys held a news conference to announce Elliott's six-year extension that made him the highest-paid running back in the NFL with $50 million in guaranteed money. Elliott reiterated he was glad the deal was finished in time for him to play Sunday and keep him with the Cowboys potentially for the rest of his career.

Next up would appear to be Prescott, although there have not been many discussions recently. Talks with Cooper have been slow all summer, but Jones said things could come together quickly with the receiver as well.

Prescott is set to start the regular season on Sunday on the final year of his rookie contract, making $2.02 million.

On Tuesday, the Los Angeles Rams signed quarterback Jared Goff to a four-year, $134 million deal that included $110 million guaranteed, according to sources. Earlier in the offseason, the Philadelphia Eagles signed Carson Wentz to a contract extension worth $32 million per season and $107 million guaranteed.

Goff and Wentz were the top two picks of the 2016 draft class. Prescott went No. 135 overall, in the fourth round.

Jerry Jones has made it clear the Cowboys want to keep Prescott for the long term. Prescott has said he wants to remain a Cowboy for the long term. Coming to an agreement on the financial terms is never easy. One issue is that Goff and Wentz were each guaranteed roughly $27 million over the 2019 and 2020 seasons as part of the fifth-year options on their rookie deals. Prescott has no guaranteed money remaining on his deal, which makes reaching the $110 million and $107 million guarantee thresholds a little more difficult.

Prescott has started every game in his first three seasons, something Goff and Wentz cannot say. Since 2016, Prescott has 32 wins, fewer than only Tom Brady. Prescott has not thrown for 4,000 yards or had more than 23 touchdown passes in a season. Goff has had 60 touchdown passes over the last two seasons and threw for 4,688 yards last season, when he helped the Rams to the Super Bowl. Wentz was having an MVP-type season in 2017 before suffering a knee injury.

Prescott's focus, however, is not on the contract. It is on the Giants and the upcoming season.

"Obviously I want to see it done," Prescott said. "To put a time frame on it, I think I've said this before, I'm not going to do that. At this point my focus is all on the Giants and the Giants defense and what this team needs to do to win the game. And next week it will roll to the next opponent. I don't want to blur my mind or distract myself any with thinking about those talks or thinking about what's going on when I've got enough on my plate to handle. So I'm just focused on the Giants and I've got people to take care of [the contract]."

As for seeing Elliott's contract situation get resolved, Prescott was happy to know he will have his backfield mate next to him on Sunday.

Elliott wants the Prescott deal to get done, too.

"I want to play with him for the rest of my career," Elliott said. "I'm excited to see what comes."

The Cowboys signed Lawrence to a five-year, $105 million deal in April with $65 million guaranteed. Before signing Elliott, they reached contracts with Smith ($35.5 million guaranteed) and Collins ($35 million guaranteed).

The Cowboys' design was to "keep a really good young football team together," Stephen Jones said.

"As I've said, we spent a lot of work on our financial models for the next three years. Certainly staring down a labor agreement in the eyes, we hope. We don't have one, got work to do, but you're factoring all those things in. But obviously we're making moves that every step of the way we think that we cannot only do what we've done, but also, as we've said, sign Dak and sign Amari."