Randall Cobb has agreed to a four-year contract to return to the Green Bay Packers. He'd been widely expected to hit the open market and be one of the most sought-after free agents (he was No. 8 on our big board) next week, but things took a surprising turn on Saturday evening. The deal allows Green Bay to keep what may be the NFL's best receiving corps together for reigning MVP Aaron Rodgers. Here are a few things to know about Cobb's deal.

1. The money: Cobb's four-year pact is worth $40 million, with $17 million of that sum guaranteed. Green Bay is, as ever, in excellent cap situation, as the Packers entered the three-day "legal tampering" window with over $33 million in cap space. They'd presumably still like to re-sign tackle Bryan Bulaga, defensive tackle Letroy Guion and one or both of Davon House and Tramon Williams as well.

There were reports throughout the day Saturday that if Cobb were to return to Green Bay, he'd be doing so on a contract worth significantly less than he would have received elsewhere, and that's apparently what happened here:

With a $10 million average annual value, Cobb's contract ties him with Brandon Marshall as the ninth-highest paid wide receiver in the league, just ahead of teammate Jordy Nelson, who checks in at $9.76 million per year. If Percy Harvin is released as is expected, Cobb would move up to eighth in AAV.

2. The reaction: Various players in and around the league showed Cobb the love after his new deal was announced.

Lang is presumably referring to the fact that Cobb is the first of a few notable free agents Green Bay is looking to re-sign, including his linemate Bulaga, as mentioned above.

Randall Cobb is staying with the Green Bay Packers. (Getty Images)

3. Cobb's career: Green Bay drafted Cobb out of Kentucky with the 64th overall pick in the 2011 draft. He was a (part-time) quarterback for the Wildcats, but the Pack picked him with the intention of making him exactly the kind of versatile offensive weapon -- lining up out wide, in the slot and even in the backfield -- he's become for them. 

Cobb was used sparingly on offense as a rookie; he played only 290 snaps in 15 games. He did most of his damage that season as a return man, bringing back both a punt and a kick while averaging 11.4 yards per punt return 27.7 yards per kick return. He did manage to snag 25 passes for an additional 350 yards and a score, however.

Cobb broke out in his second season, catching 80 passes for 954 yards and eight touchdowns while still having his snaps limited to just 651 in 15 games. Pro Football Focus graded him as the NFL's 11th-best wide receiver that season, and his 78.4 percent catch rate ranked second among NFL wideouts behind only Brandon Stokley. Aaron Rodgers' 119.4 quarterback rating when throwing to Cobb in 2012 was the 11th-best quarterback-to-receiver rating in the league, despite being only third-best on Green Bay. That was also the first season where we got a real glimpse of Cobb's slot receiver prowess. His 62 receptions from the slot were second to only Wes Welker, while his six slot touchdowns were third in the league and he paced the field in Yards Per Route Run from the slot.

The 2013 season saw Cobb suffer his first major injury, a broken leg. He missed 10 games before returning for the season finale and catching a 48-yard touchdown pass that sent Green Bay into the playoffs. He wound up with 31 catches for 433 yards and four touchdowns overall.

Cobb's 2014 season was his best one yet. He caught 91 passes for 1,287 yards and 12 touchdowns. Those figures ranked eighth, 11th and fourth among wide receivers, respectively. Cobb caught 72.8 percent of the passes thrown his way, 10th-best among wideouts, and forced 18 missed tackles, second to only Golden Tate and Steve Smith, who led receivers with 20 misses tackles forced.

Rodgers registered a quarterback rating of 134.3 when throwing to Cobb in 2014, the best figure of any quarterback-receiver tandem in the NFL. In the second half of the season, he emerged as Rodgers' top weapon, being targeted 105 times to Jordy Nelson's 92, according to Mike Clay of PFF and ESPN. Cobb was once again a monster in the slot, leading the NFL with 75 catches, 1,067 yards, 12 touchdowns and 2.13 Yards Per Route Run when lined up in the slot, which he did on 87.3 percent of his pass routes.

This contract takes him through his age-28 season, meaning he'll have the chance to hit the open market again before his production starts to precipitously decline.

4. The wide receiver market: With Dez Bryant and Demaryius Thomas receiving the franchise tag and Cobb heading back to Green Bay, the top three wide receivers on our free agent big board are all off the market. That's good news for those that remain, such as Jeremy Maclin (19), Torrey Smith (21) and Michael Crabtree (50), as well as players who recently became available like Reggie Wayne or might become available like Andre Johnson and/or Percy Harvin.

This year's draft class once again looks deep at wide receiver, but teams often use free agency to fill their holes before using a best player available strategy in the draft. There are a lot of different types of wideouts still out there for the taking, and Cobb has set the market price fairly high. That he's a slot receiver will also certainly come up in the negotiations for the remaining players, as slot guys have typically received lesser contracts than receivers who play the majority of their snaps on the outside.