NFL free agency begins Monday, March 7, though teams are not allowed to officially sign a player until after 4 p.m. ET on Wednesday, March 9. Three teams expected to draw attention are the Green Bay Packers, a perennial contender with seven straight postseason appearances, along with their NFC North rival the Chicago Bears, as well as the rebuilding Oakland Raiders.

The Bears and the Raiders should envy Green Bay’s position as perennial contenders, but not their limited funds. Chicago’s third in the league behind Oakland with more than $60 million in cap space, while the Raiders are second with $74.1 million, roughly $500,000 less than NFL-leader Jacksonville, according to figures compiled by

Green Bay Packers

The Packers have garnered the reputation of building through the draft rather than the NFL’s free agency market. The Packers could, however, slightly veer off course and be major players once free agency begins.

"We’ll see how it shakes out," Packers head coach Mike McCarthy told reporters Thursday. "We might shock you this year."

In which way the Packers may "shock" the league remains to be seen, but Green Bay is expected to target one glaring weakness: offensive line.

Star quarterback and two-time NFL MVP Aaron Rodgers was sacked 46 times last season, ranking among the most takedowns by any passer in the league.

Green Bay dealt with significant injuries in front of Rodgers, and may opt to gamble on their tackles and guards staying healthy next season. Or they could pursue the likes of Chicago’s Jermon Bushrod, former New York Giant offensive tackle Will Beatty, or even Seattle’s Russell Okung, all of whom are unrestricted free agents.

Still, Packers general manager Ted Thompson doesn’t exactly have unlimited resources. The Packers have a little over $21.5 million in salary cap space, just the 22nd highest total among all teams prior to the start of free agency, and there are several players who already call Lambeau home up for new deals.

Green Bay will have to find cap space to keep linebackers Michael Neal and Nick Perry, strong safety Sean Richardson, and defensive tackle B.J. Raji. If not, it’s possible one or several of those top producers could be allowed to walk and Thompson uses the extra funds to protect Rodgers.

Chicago Bears

The Bears have nearly two times more wiggle room than the Packers, but general manager Ryan Pace still faces difficult decisions. In fact, he already made some by opting to part ways with both running back Matt Forte and Bushrod, and he could do the same with star leading receiver Alshon Jeffery.

Pace is widely expected to help head coach John Fox build a top defense just like he did with Denver and Carolina. The Bears were ranked No. 4 in total defense last season, but their pass rush was just No. 22 with 35 sacks and they accumulated a mere 17 turnovers, No. 28.

The Bears clearly need to spruce up their pass rush and defensive backfield, and they have the funds to pursue current Chiefs safety Eric Berry or cornerback Sean Smith, but the pass rusher market is a bit thin this year.

Top sack artists like Denver’s Von Miller are expected to either reach long-term extensions or teams will place their franchise tag on them. Teams have until March 1 prior to 4 p.m. ET to place the tag, which gives players a one-year deal at a specified amount that falls in line with the rest of the top players at their position.

However, that still means Chicago could take advantage of a team like the Miami Dolphins, who may have to let defensive end Olivier Vernon walk due to a very tight salary cap. Miami has a mere $8.7 million in space prior to the start of free agency.

Oakland Raiders

The Raiders are in the same boat as Chicago, a ton of cap space that could either help them immediately if used wisely or perhaps stashed away for next year. Oakland finished No. 22 in total defense, but has some excellent pieces to build around like first-team All-Pro linebacker Khalil Mack.

In order to help out Mack, the Raiders must address their No. 26 ranked pass defense, which coughed up 259 yards per game last season and their pass rush was very middle of the road at No. 14 overall with 38 sacks.

Denver Broncos defensive end Malik Jackson might be a top target for the Raiders, though he may cost $12 million dollars per year. Berry, Vernon, and Smith are also reasonable avenues for Oakland to pursue, but it could cost them left tackle Donald Penn as budding quarterback Derek Carr appears ready to join the NFL’s elite group of passers.

Penn, 32, is scheduled to be an unrestricted free agent and given his age and Oakland’s needs in other areas he could be gone.

“There’s a time for play,” Raiders head coach Jack Del Rio told the San Francisco Chronicle, “and there’s a time for pay. This is the time for pay part.”