Dallas Cowboys tight end Jason Witten underwent another exam Tuesday on his slightly lacerated spleen and is healing progressively.

Witten's status, however, remains in question for the regular-season opener against the New York Giants on Sept. 5.

"He had a positive report from the doctors yesterday," Cowboys coach Jason Garrett said. "His spleen is healing, it is getting better. His work on the field has become more extensive, he's been running, he's been catching balls. We're hopeful that he can do something as the practice week starts on Saturday. We'll just continue to make that evaluation. He's going to be evaluated by doctors for a while."

Witten has missed only one game in his NFL career, due to a broken jaw, and the Cowboys are preparing backups John Phillips and rookie James Hanna to replace him against the Giants if he can't play.

Doctors are checking Witten's blood work on a daily basis to measure how well the laceration of the spleen is healing.

In what was considered a good sign toward his progress, Witten was doing some rehab work on Monday before the team's practice. After Witten was injured on Aug. 13, doctors told the seven-time Pro Bowler that he would be under limited movement for a week to 10 days.

"It's something that's ongoing," team executive vice president Stephen Jones told KRLD-FM on Wednesday. "He had a good appointment yesterday, looks like things are progressing, and we'll take another look next week."

Jones said that Witten will undergo another exam early next week and that surgery hasn't been ruled out yet.

Meanwhile, cornerback Mike Jenkins was removed from the physically unable to perform list Wednesday, clearing the way for him to possibly play against the Giants despite missing the entire offseason, training camp and four preseason games because of right shoulder surgery in January.

The Cowboys will have a walkthrough Thursday before an off day Friday. The first full practice for the Giants will be Saturday. Had Jenkins remained on the physically unable to perform list after Friday's final cuts, he would have missed the first six games of the season.

Information from ESPNDallas.com's Todd Archer was used in this report.