The NFL’s version of the hot-stove league heated up Monday with the trades of a pair of Pro Bowl wide receivers to NFC West teams.

But the biggest Panthers’ news involved former cornerback Chris Gamble, who retired three days after the team cut him to get under the salary cap.

On the eve of free agency, which begins at 4 p.m. Tuesday, the Panthers made two roster moves – tendering a 1-year, exclusive rights contract to tight end/fullback Richie Brockel and announcing the re-signing of backup linebacker and special teams captain Jordan Senn.

Senn told the Observer last week he’d agreed to a 1-year deal.

Given their cap position, the Panthers are expected to be relatively quiet at the start of free agency.

Releasing Gamble put the Panthers about $4 million below the $123 million cap. Team officials have asked veteran left tackle Jordan Gross to take a pay cut that would further assist them in freeing money to use on signing free agents and their draft picks.

Gamble, a nine-year veteran whose 27 interceptions are the most in team history, had a cap figure of $10.9 million this year. Figuring in the accelerated bonus money over the final two years of Gamble’s deal, the Panthers created $7.9 million in cap space by releasing him.

“I anticipated a salary cap issue. I didn’t know what it would turn out to be,” Carl Poston, Gamble’s agent, said Monday. “I didn’t know if it was going to be a restructure or total release or where it might go.”

Despite drawing interest from multiple teams, Gamble decided to retire with both his health and personal wealth in good shape. He called Poston on Sunday night to inform him of his decision.

“Given that so many players retire broke, Chris has been good with his money. He’s been frugal with the way he does things economically,” Poston said. “This is just an extension of him planning his life after football.”

Gamble, who turned 30 on Monday, missed the final 12 games last season with a torn labrum that required surgery. He also missed time with injuries in 2010 when he fell out of favor with former coach John Fox.

But Gamble bounced back with a strong season in 2011 when new coach Ron Rivera challenged him by putting him on the opponent’s top receiver each week. Gamble responded by allowing a reception once out of every 18.1 snaps in coverage – the second-best ratio in the league, according to ProFootballFocus.com.

Captain Munnerlyn, who played with Gamble for four seasons with the Panthers, was surprised by his decision to retire.

“Dang can’t believe Gamble done,” Munnerlyn tweeted, calling Gamble “one of the best cornerbacks in the NFL.”

Gamble never went to the Pro Bowl, but the first-round pick from Ohio State in 2004 made 117 regular-season starts – the most by a cornerback in team history – after the Panthers drafted him.

The Panthers could lose both of their veteran corners if they don’t re-sign Munnerlyn, who is eligible for free agency for the first time. Munnerlyn has said he’d like to remain with Carolina, although first-year general manager Dave Gettleman is expected to take his time to see how the crowded cornerback market plays out.

The Panthers drafted a corner last year when they took Coastal Carolina’s Josh Norman in the fifth round. But their top three corners are 25 or younger, so it’s likely Gettleman will look for a veteran in free agency.

A pair of proven wideouts changed teams Monday when Seattle acquired Minnesota receiver/returner Percy Harvin and San Francisco traded a sixth-round pick to Baltimore for Anquan Boldin, one of the heroes of the Ravens’ Super Bowl season.

With Senn re-signing, the Panthers have 10 players set to become free agents Tuesday afternoon. The list includes tight ends Gary Barnidge and Ben Hartsock, although Brockel’s tender could mean at least one of the tight ends will not be back.

Hartsock, 32, is a blocking tight end who had two receptions for 30 yards the past two seasons. Barnidge caught six passes for 78 yards and a touchdown last season after he missed the 2011 season with a broken ankle.

Brockel is known for his blocking and versatility, although his most memorable moment came in 2011 when he caught a touchdown pass at Houston on a fumblerooskie play called the Annexation of Puerto Rico. Rivera joked the Panthers came up with the play from the 1994 movie “Little Giants.”