Chad Greenway is unsure if Sunday will be the last game of his NFL career.

Greenway, the 33-year-old Vikings linebacker, entered the 2016 season with the intention of walking away after playing out a one-year contract signed in March. However, Greenway said he’s still entertaining the possibility of returning for a 12th NFL season. It’s a “family decision,” Greenway said, and one that will be made after Sunday’s game against the Bears at U.S. Bank Stadium.

“Then we can take some time to think about it and reflect and make sure we’re all in a position where we know what we want to do,” Greenway said.

Sunday will mark Greenway’s 156th game for the Vikings, which ties him for the 15th-most appearances by a defender in a purple and gold uniform.

Only mainstays such as Jim Marshall, John Randle and Kevin Williams have stuck longer in Minnesota. Greenway said he has sought advice from former teammates about the decision to retire from football.

“I don’t think you get to this position and been through 11 years of this grind and it’s just easy to say, ‘Well, I’m done,’ ” Greenway said. “It’s a tough decision, it really is.”

Greenway, a full-time starter for eight seasons from 2007 to 2014, has seen a lessened role the previous two seasons following the team’s selection of Eric Kendricks in 2015’s second round. Greenway has played 40 percent of the Vikings’ defensive snaps this season as the third linebacker in the base defense.

“Not everybody gets the opportunity I’ve had,” Greenway said. “So I cherish that and try to keep things in perspective. I just want to make the decision when it’s right. I don’t want to take away from this week.”

Peterson’s status uncertain

Adrian Peterson’s status is uncertain for Sunday’s season finale against the Bears. Peterson did not play Saturday at Green Bay because of knee and groin injuries, the latter of which happened in his first game back, Dec. 18 vs. Indianapolis, from September knee surgery.

Peterson told reporters earlier this month he would not risk further injury “for obvious reasons,” if the Vikings were eliminated from playoff contention.

“We’ll have to see how he is health-wise and everything else,” coach Mike Zimmer said.

Also uncertain is Peterson’s long-term future with the Vikings. He is due a non-guaranteed $18 million next season in the final year of his current contract.

Peterson, the Vikings’ all-time leading rusher, has gained just 72 yards on 37 carries in three games.

Unbeaten to ‘average’

The NFL’s last unbeaten team has nothing but pride to play for during this weekend’s season finale. A .500 finish is the best the Vikings can hope for now in a season full of twist and turns, from Teddy Bridgewater’s season-ending injury to Norv Turner’s resignation to the previous two defensive collapses against the Colts and Packers.

“You can do some really good things, but if you can’t do them all the time, you’re average,” Greenway said. “Which, if we win, we’re 8-8. That’s average.”

They have skidded off track with a 2-8 record in the last 10 games.

“I’m disappointed in where we are in the season,” Zimmer said.

2017 opponents set

As the third-place team in the NFC North, the Vikings’ opponents have been determined for next season.

They will play the entire NFC South and AFC North. For a second year in a row, the Vikings will travel to Washington. Nondivisional road trips will include the Falcons, Panthers and Steelers.

The Vikings are also scheduled to be the visiting team against the Browns in one of four NFL games in London.

The Vikings will play host to the Ravens, Buccaneers, Saints, Bengals and Rams at U.S. Bank Stadium.