Special teams will have their work cut out

The Vikings have given up five special-teams touchdowns in seven games and rank last in the NFL in opponents' punt return yardage.

That's good news for Houston's Jacoby Jones, who is second in the league to New Orleans' Reggie Bush with a punt return average of 14.7 yards. Jones also has two returns for touchdowns.

"He's very explosive, he does a good job setting angles up and then cutting it back," said Vikings linebacker Vinny Ciurciu, who plays on all special teams. "We definitely have to be on point on making sure we're not going to overguess and try to cut him off, because he's just going to stick a foot in the ground and shoot right up the field. He does a great job cutting back and just exploding through holes."

Ciurciu said an area of focus on punt coverage has been making sure players are not grouped together so returners can't get away from a pack of would-be tacklers at once. Chris Kluwe, who dropped a snap that led to a touchdown in the Vikings' 48-41 loss at Chicago, has continued to work on his directional punting.

The Vikings, who are 30th in the league in kickoff coverage, should get a boost with rookie safety Tyrell Johnson playing on all phases of special teams beginning Sunday.

Johnson had been used only on kickoffs, but he is freed up now that Madieu Williams is expected to take over as the starting safety after recovering from a neck injury. Johnson started the first seven games at safety.

"If you are a starting safety in this league you certainly should be able to help on special teams," special teams coordinator Paul Ferraro said of Johnson. "I look forward to getting him more involved."

Linebacker Ben Leber will continue to wear the communication device in his helmet that enables him to receive defensive signals from the sideline, even though Napoleon Harris has taken over as the starter at middle linebacker.

Leber inherited that responsibility after middle linebacker E.J. Henderson suffered a season-ending foot injury.

Leber said making the defensive calls in the huddle has been an adjustment, but he is more comfortable with it.

"It's a lot tougher than it sounds," he said. "E.J. had a tough job. I'm just trying to go in there and do the best job that I can."

Safety Darren Sharper said Leber has done a good job with the communication.

"He has a lot more baritone in his voice than E.J.," Sharper said. "I definitely can hear him better on the field than E.J. E.J. is a quiet guy who kind of whispers."

• WCCO (Ch. 4) agreed to purchase the last "several hundred" tickets to the Vikings game Sunday against Houston, meaning it will be televised locally on the CBS affiliate. The station will donate the tickets to local military personnel and their families, according to Vikings vice president of sales and marketing Steve LaCroix.

• Vikings linebacker David Herron (hip) did not practice for a second consecutive day Thursday. Defensive end Ray Edwards (knee), tight end Garrett Mills (ankle), wide receiver Sidney Rice (knee) and Williams (neck) were limited.

• The Vikings are planning a video tribute and a moment of silence for former Vikings safety Karl Kassulke before Sunday"s game. Kassulke died of a heart attack Monday at his Eagan home. He was 67.