Martellus Bennett demolishes Jon Gruden on Twitter

Martellus Bennett ended a 10-year NFL career this spring, but his comments on Oakland Raiders coach Jon Gruden may have been his hardest hit ever.

In the overall scheme of the NFL universe, Jon Gruden and Martellus Bennett are even in the category of Super Bowl rings, Gruden winning one as head coach of the Tampa Bay Buccaneers after the 2002 season and Bennett picking up his with the New England Patriots in 2016.

But Bennett, a former Pro Bowl tight end who played with five NFL teams over a 10-year career, may have delivered his most devastating hit of all when asked on Twitter whether he would want to play for Gruden.

So, Martellus, don’t mince words. Tell us what you really think.

Bennett was never shy about expressing himself during a career that included stints with the Dallas Cowboys, New York Giants, Chicago Bears, New England Patriots and Green Bay Packers. Bennett was a Pro Bowler for the Bears in 2014.

He retired in March after 10 seasons with 433 receptions for 4,573 yards and 30 touchdowns in order to focus on his multimedia company, The Imagination Agency.

Gruden’s return to the NFL coaching ranks this year after nine seasons in the broadcast booth on ESPN’s Monday Night Football has not gone particularly well. OK, it’s been an unmitigated disaster on and off the field.

The Raiders lost 42-28 Sunday to the Indianapolis Colts at Oakland Coliseum to fall to 1-6 on the season, with their lone win coming in overtime against the Cleveland Browns — that noted paragon of management stability that fired both their head coach and offensive coordinator Monday.

That was the third straight loss for Oakland, which is ranked 17th in the NFL in total offense and 26th in total defense and is 31st in the league having surrendered 31.1 points per game.

And then there was the trade of two-time All-Pro linebacker Khalil Mack to the Bears for a package of draft picks that included first-rounders in 2019 and 2020 along with a sixth-round pick in 2019 and a third-round selection in 2020.

Did we mention the Raiders also surrendered second- and fifth-round picks in 2020 as part of the deal?

That for a player who had registered 37½ sacks over the last three seasons, but refused to report to training camp in July because he wanted a new contract. Oakland had exercised its fifth-year option on Mack’s rookie deal in April, but the sides were far apart on a possible extension.

Chicago immediately locked up Mack to a six-year, $141 million extension after acquiring him and he’s responded with five sacks, an interception and four forced fumbles in six games before sitting out Sunday’s win over the New York Jets with a sprained ankle.

Oh, and after winning 14 games in the last three seasons and not having made the playoffs since 2010, Chicago is 4-3 and leads the NFC Central by a half-game over the Minnesota Vikings.

Oakland has the worst record in the AFC and is a half-game ahead of the San Francisco 49ers and Giants, neither of whom has had their bye week yet.

It’s fair to speculate that if Bennett, a recently retired former player, feels that way about Gruden’s NFL return, there are probably guys in his own locker room that share similar sentiments.