San Francisco 49ers defensive tackle Ian Williams suffered a serious ankle injury on what Jim Harbaugh believes was a "legal" play.

Patrick Willis evidently feels that the NFL should evaluate its stance on cut blocks especially after Williams' injury in Sunday night's loss to the Seattle Seahawks.

"I feel like as a linebacker or a D-lineman any cut it's a man sport -- be a man hit me up high" Willis told "Hit like rams. You don't see a ram going and cutting another ram's legs. They hit head to head pad to pad."

Williams has a broken ankle a league source told ESPN NFL Insider Adam Schefter. He was injured when he was being cut blocked by Seattle's J.R. Sweezy midway through the first quarter Sunday.

Harbaugh said he did not know whether Williams' ankle was broken but acknowledged that Sweezy's block was "legal the way the rules are set up."

But Willis obviously is not a fan of the rule.

"I feel like that's something the league should look into more" he told "You see some of that stuff and it's uncalled for.

"You have a guy who's 300 pounds cutting a guy who's 250 pounds. Do physics to that. Hit the man up high. It should be a good collision."