Defensive end Brian Robison had been showing off his, ahem, backside in the locker room to pretty much everyone this week, so Friday he wanted to make sure a few reporters got to check it out, too.

Robison suffered a bruise on his buttocks, an injury the Vikings have politely listed as a gluteal injury on the official report all week. He is probable to play Sunday against the Washington Redskins, but the injury has caused him discomfort all week.

"Did you see it? It hurts as bad as it looks," Robison said.

The bruise, suffered when a Tampa Bay Buccaneers player accidentally kneed him last Sunday, is the size of a football and continues to expand, providing daily entertainment to curious teammates.

Robison felt better as the week went on. The good news is that he experienced less pain and tightness in the injured area when he was running around at practice. Sitting on the bruise during meetings was the more painful job responsibility.

"That's probably the worst part of my day," said Robison, who has sat out only two games because of injury in eight NFL seasons.

Coach Mike Zimmer said Robison "should be good to go" by Sunday.

Relative health

Cornerback Jabari Price is the only Vikings player in question for Sunday. He was officially listed as questionable because of a hamstring injury, though he did practice on a limited basis for a second consecutive day.

Tight end Kyle Rudolph was officially ruled out and will return sometime after the bye week.

Five players, including cornerback Josh Robinson (ankle) and defensive tackle Sharrif Floyd (ankle/knee), are probable.

Besides losing Rudolph to his sports hernia injury and placing quarterback Matt Cassel (broken bones in foot) and guard Brandon Fusco (torn pectoral muscle) on injured reserve, the Vikings are actually relatively healthy right now.

"We're starting to get healthier, yeah," Zimmer said. "We obviously lost some guys for the year. But the guys who were nicked up are starting to get healthier."

Not strong enough

With Vlad Ducasse inactive against the Buccaneers, Joe Berger replaced him in the starting lineup (Berger is expected to start at right guard again Sunday). Undrafted rookie Austin Wentworth was activated as one of the two backup linemen over fifth-round draft pick David Yankey.

Zimmer said Yankey, who has yet to suit up this season, needs to get stronger before he can be counted on.

"He's doing OK with the technique and understanding," Zimmer said. "He's got to get stronger. He's got to be more stout in the areas where he needs to be."

Leery of Jackson

Wide receiver DeSean Jackson, who signed with Washington this offseason after six seasons in Philadelphia, is one of the NFL's fastest players and among the league's most feared deep threats.

Jackson leads all qualifying receivers with an average of 20.8 yards per reception and his seven receptions of 40-plus yards are three more than any other receiver.

"He's got great speed, great quickness, great acceleration, so yeah, he's stressful," Zimmer said.

(Usually) braving cold

The Vikings held a rare practice in their indoor practice facility Thursday. But Zimmer plans to usually have the Vikings practice outside, even when the temperatures fall below freezing, to prepare them for outdoor games at TCF Bank Stadium and road venues such as Chicago's Soldier Field.

"If we're playing in Miami, we're probably not going to be outside," Zimmer said Thursday. "If the weather's bad and we can't get stuff done, that's one thing. But if we can get out here, I'll have some heaters out here going, and we'll try to get out here. In Cincinnati, we didn't have an indoor [practice facility]. We had to go outdoors. It is what it is."