The NFL essentially commanded defensive players to avoid violent collisions to the head in recent years, and now nasty knee injuries have littered locker rooms, especially this season.

In Week 14, Arizona Cardinals rookie safety Tyrann Mathieu ripped his ACL and LCL, upping the number of season-ending knee injuries to at least 41 this year, a 64 percent jump since 2011, according to Bloomberg.

In the face of questions about his character off the field at LSU, Mathieu emerged as an excellent third round pick, ranking second on the team with 68 total tackles and two interceptions. The Cardinals are fourth in total defense this season, and in many leagues has scored the fifth most points for fantasy owners.

The loss of Mathieu may hurt the Cardinals and their playoff hopes going forward, but owners shouldn’t think twice about starting them for the rest of the year. Arizona still has a sleeper Defensive Player of the Year candidate in linebacker Karlos Dansby (105 tackles, 6.0 sacks, 3 INTs, 16 passes defended), along with corners Jerraud Powers and Patrick Peterson (26 passes defended, 4 INTs combined).

That’s without mentioning their Week 15 opponent in the Tennessee Titans, a team that’s lost four of its last five games and who’s top running back Chris Johnson is averaging 3.8 yards per carry. Plus, quarterback Ryan Fitzpatrick has tossed four interceptions in the last two games.

Arizona does have an uphill battle at Seattle and home against San Francisco in Weeks 16 and 17, but for now they’re a terrific option for fantasy owners.

Checkout the other defensive picks of the week below.

Washington Redskins

Yes they’ve lost five straight, and the supposed love-hate triangle between quarterback Robert Griffin III, head coach Mike Shanahan, and owner Dan Snyder has dominated the headlines. Reportedly Kirk Cousins may start over RG3, supposedly for health reasons.

But Washington faces the even lower 3-10 Atlanta Falcons, who have struggled all season on both sides of the ball. Consider the Redskins a third option if Arizona or the below teams aren’t available.

Philadelphia Eagles

The Eagles are the hottest team in the league with Carolina and Seattle’s winning streaks ending in Week 14. Philadelphia is letting up 18 points per game and have won the turnover battle 12 to 1 against opponents for five straight wins.

And Adrian Peterson may not play for Minnesota, a huge plus for Philadelphia’s playoff chances and owners.

Buffalo Bills

They’ll face a Jacksonville team that’s won four of their last five, but two of those wins were against 2-11 Houston. The Jaguars also were outgained in total yards in four of those games, and let up 400-plus yards three times.

The Bills have had their fair share of struggles this season, losing five of the last six. But with three defensive touchdowns, 18 INTs, and 43 sacks this season, the Bills are still a viable threat for fantasy owners.

Miami Dolphins

New England lit them up for 27 points in Week Eight, but the Dolphins are a sleeper after winning three of their last four, including two straight on the road, and are now a game back of making the playoffs. The Patriots will be limited with tight end Rob Gronkowski out, and Miami has proven they can wreak havoc on opposing quarterbacks.

According to FFToday, the Dolphins are sixth in the league against passers, which could spell trouble for the Pats and Tom Brady, but be a huge coup for a fantasy owner hoping to make the championship round.