Michael Bennett has made a bunch of money the past couple of weeks — without playing a down.

If there were any doubt Bennett deserved a raise on his bargain-basement deal, the past three games have wiped it out.

Long upset over his undervalued contract, Bennett nonetheless had showed up and played great for the last two seasons-plus. But now a knee injury has forced him into an involuntary holdout that has shown everyone just how underpaid he is.

When Bennett was healthy (aside from his ongoing toe problem) in the first five games, the Seahawks were leading the league in third-down defense (29.9 percent) and overall defense (284 yards per game) and were third in rush defense (75 yards).

But Bennett suffered a knee injury against Atlanta in Week 6, and the Seattle defense hasn’t been the same since. He played the next week against Arizona but had little effect on the game. He then was inactive against New Orleans in Week 8 and had surgery after that game.

Ever since Bennett was injured, Seattle’s defense simply has not been able to get off the field enough. They have gone 1-1-1 against Arizona, New Orleans and Buffalo — giving up 414 yards (139 rushing) and 27 first downs per game while allowing 58.5 percent on third downs.

It took all they could muster to put together a game-saving goal-line stand Monday vs. Buffalo.

The obvious factor is Bennett’s absence. After all, he is one of the very best all-around defensive linemen in the NFL and Frank Clark, Cassius Marsh and the rest have not been able to pick up the slack (although Damontre Moore had a nice debut Monday).

The Seahawks likely will be without Bennett for another couple of games. Their game in New England on Sunday night figures to be yet another argument for paying the Pro Bowl player.

Bennett, who turns 31 on Nov. 13, has been working off a four-year, $28.5 million contract since 2014, and he reportedly wants $14 million a year. It’s a big number, but it fits the market for top D-linemen and also can fit under the Seahawks’ 2017 salary cap.

In August, Pete Carroll told KJR they were “working at” keeping Bennett beyond 2017.

“It’s a very difficult thing to get done,” he said.

But it should get easier with every game Bennett misses — because the Seahawks miss him badly.