GREEN BAY, Wis. (AP) -

The Packers rookies who have made two of the strongest impressions this preseason weren't at the top of the team's draft board.

Productive performances by seventh-round pick Jeff Janis and undrafted free agent Jayrone Elliott in Thursday night's 34-14 preseason win over the Oakland Raiders may have cemented their spots in Green Bay. Teams must trim rosters to 53 players by Saturday afternoon.

"I knew that I had to perform and show once again what I could do. I feel really good about the game and I'm just going to hope for the best," said Janis, a receiver who had a 33-yard touchdown catch and 62-yard kickoff return to set up another score.

The main story line for the Packers will be whether coach Mike McCarthy decides to keep both Matt Flynn and Scott Tolzien to back up starting quarterback Aaron Rodgers. That would give McCarthy two good insurance policies if Rodgers goes down for any length of time, as he did last season for seven weeks with a collarbone injury.

Tolzien has shown enough talent that he would likely be signed by another team if left on the Packers' practice squad. But the down side with keeping three quarterbacks is that it would take up a valuable roster spot for someone unlikely to play barring injury, whereas keeping a player at another position would allow the Packers to use that man on special teams.

It's already game week in Green Bay with the season opener on Sept. 4 in Seattle against the Super Bowl champion Seahawks looming. But McCarthy was going to take every minute available to make the roster decisions.

"Absolutely. The most important thing we have in front of us is picking this roster," McCarthy said.

The 6-foot-3 Janis appears to be in good shape. It's impressive for someone from Division II Saginaw Valley State who missed the first week of camp because of illness.

"I think I showed what I can do and I knew it was something in this game that I had to showcase a little bit more. I think I did pretty well," Janis said.

So did Elliott, a longshot linebacker from Toledo who recorded his fifth sack in three preseason games. That includes three in four plays two weeks ago against St. Louis.

But the first four sacks occurred late in games. Thursday's takedown came after Elliott pushed first-string right tackle Donald Stephenson into the pocket before putting his hands on the quarterback with the Chiefs backed up against their own goal line.

It was the most extensive playing time yet for Elliott, who cramped up at one point in the second half.

"His body of work has been very good," McCarthy said.

Janis and Elliott might bolster positions that already have good depth.

Jordy Nelson and Randall Cobb lead the Packers receiving corps, and Jarrett Boykin appears to have locked down the third receiver position. Second-round pick Davante Adams also had a touchdown against the Chiefs.

At outside linebacker, the Packers have a healthy Clay Matthews to go with free agent addition Julius Peppers. Mike Neal and Nick Perry also figure to work regularly into the pass rush rotation.

They might have to make room for Elliott, too.

"You never know. I'm probably going to go catch a movie with the guys and take my mind off it," he said. "The one thing I wanted to do when I came here was to leave everything I had and just get better every day, and I think I accomplished that."