The Arizona Cardinals possess one of the most elite special teams units in the NFL, which gives Ken Whisenhunt's squad a deathly weapon to bestow upon their opponents.

The Cards have shown they can deftly block punts, field goals, extra points and have the weapons in Patrick Peterson and LaRod Stephens Howling to potentially take it to the house on every return.

Special teams coach Kevin Spencer told Arizona Sports 620's Doug & Wolf Show Friday he recognizes he's coaching a group of players that are quite dangerous.

"I think with our specialists, who are playing well, and our return specialists, although we've had scant opportunities, I think we are on the cusp of busting out there," Spencer said. "We have the ability to block punts, we obviously have the ability to block field goals and we got everybody dialed in and they care and they are working hard."

Linebacker Quentin Groves blocked a punt on the Patriots' 10-yard line in last Sunday's 20-18 upset win. Calais Campbell blocked a 50-yard field goal attempt against the Seahawks in Week 1. The Cardinals rank first with two blocked kicks this year.

Spencer is well aware of the fact that he's working with a group of guys that are, well, special.

"I don't think it's being a bragger or a cocky person to say that I think I am coaching one of the finer units in the NFL," Spencer said.

When the Cardinals take on the Philadelphia Eagles Sunday at University of Phoenix Stadium, they have a clear edge over their counterpart. The Eagles haven't blocked a punt since Jevon Kearse did so in November 2004 and their last blocked field goal came against the Redskins on January 1 of last year.

Despite any advantages the Cardinals may have, the mark of a great unit is working hard week in, week out and never taking a play off.

"You've got to do it for 60 minutes against the Eagles," Spencer stated. "You've got to prove it every Sunday because every Sunday the other guy is trying to rip your heart out and you've got to be ready for that."