FRISCO, Texas -- In 2017, tight end Jason Witten did not have a goodbye. Nobody knows whether Sunday's game against the Washington Redskins (4:25 p.m. ET, Fox) will be a goodbye for the Dallas Cowboys’ legend either.

Witten said Thursday he "is not envisioning this being my last game," should the Cowboys' season end Sunday, mostly because during his return his approach has been to remain 100% invested.

"I didn't want that to be the mindset of, ‘OK, this is your last road game, here is your last home game, here is your last Wednesday practice,’" Witten said. "Look, I know there have been a lot of great players who have approached it that way. I've got so much respect for them. But for me, it's another day. I have so much passion for this game and what it takes. I've approached it that way this season, and I'm not going to change at this point."

Two years ago, Witten entered Week 17 knowing the Cowboys would not be in the playoffs and unsure about his future. After briefly contemplating retirement, Witten had planned to return in 2018, but the chance to work as ESPN's Monday Night Football analyst led him to walk away.

A "burning desire," to play guided him back to the Cowboys. Upon his return, Witten said he would "smell the roses" and appreciate the trappings of the game.

"If that's the case, it's not like he's blogging about it," Cowboys coach Jason Garrett said. "He's pretty locked in."

Witten's dream was always holding the Vince Lombardi Trophy after Super Bowl LIV in Miami, but he thought about every possibility in making his decision.

"The one thing I knew was this is a hard game, it's a tough league," Witten said. "I understand every time I line up it's going to be difficult, so, yeah, I was thinking about competing for a championship, but I knew it wasn't going to be easy at all times. There were going to be moments like this. That was one of the things [in] why I was coming back to be a part of this locker room. It's been a tough year. In a lot of ways, we need to play better, needed to play better."

Witten knew things would be different in his return. While he has started every game this season, he has not played every snap -- through 15 games, he has played 76.1% of the offensive snaps after playing 1,050 of 1,068 snaps in 2017. He is third on the team in catches with 59 and has 505 yards and four touchdowns, putting him in a similar neighborhood to his 2017 numbers -- 63 catches, 543 yards and five touchdowns.

"I figured he would play well when he came back just because it's so important to him," Cowboys Pro Bowl guard Zack Martin said. "He takes a lot of pride in being a guy you can count on, on the field. No surprise for me there."

His return, however, was not about more catches, yards, touchdowns or even playing time. It was the chase for an elusive Super Bowl, and barring a Philadelphia Eagles loss to the New York Giants on Sunday, Witten's season will end far sooner than he had envisioned when he walked back into the locker room last February after announcing his return.

But he signed up for it -- win or lose.

"Winning helps that a lot more," Witten said. "One of the things I think I reflect back on when I had that year off was the process that allows you to get there. Just finding ways through film study, preparation, then the group having success collectively. ... Diving in on that challenge has been very enjoyable. But look, you're measured by wins and losses. The quarterback carries that, the head coach carries that. Veteran players you throw in that category of you're measured off do you win or not. That's made it tough. I've loved every second being out there playing."

Witten, who will turn 38 in May, let younger players such as Martin, quarterback Dak Prescott and running back Ezekiel Elliott serve as the voices on offense, speaking up only when he felt it was necessary. He has helped mentor younger tight ends Blake Jarwin and Dalton Schultz and served as a sounding board for Cowboys first-year offensive coordinator Kellen Moore.

It has not gone perfectly. While Witten has made some impact plays, including his one-handed touchdown reception against the Los Angeles Rams in Week 15, he had a key drop last week against the Eagles. His 8.6 yards per catch would be a career low, but his blocking has helped Elliott to a 1,000-yard season.

The fiery nature he displayed in his first run with the Cowboys has remained. He was seen yelling on the sidelines during a poor stretch for the offense in the Week 14 loss to the Chicago Bears. After his touchdown against the Rams, he fired down a spike for one of the few times in his career.

"Everybody has their own personality and everybody is unique," Cowboys receiver Randall Cobb said. "They have their own characteristics that you take in, and he definitely embodies what it means to be a hard worker, to know what you're doing, to come out and be physical every day, to take care of his body -- all the things that a pro is supposed to do, he has all those characteristics."

Witten believes he has played at a high level. He does not believe his age has held him back. In addition to not missing a game, he has not missed a practice. He says a decision on whether to return for a 17th season will be made quickly.

Witten might not be getting a storybook finish, but his impact on the roster remains.

"If you gave the numbers and the way he's played ... and said he was going to do that, a lot of people wouldn't believe you. So credit him, but it's no surprise," Prescott said. "That's who he is, who he has been his whole career. Would hate to think it's his last one, but if it is, I'll say it over and over, he's what the star means on and off the field. Represents himself and this organization the right way. Somebody that's been a perfect demonstration for me to look up to."