Vikings coach Leslie Frazier said tight end John Carlson likely won't play Thursday after suffering concussion-like symptoms Monday.
Carlson took a helmet-to-helmet hit Sunday from Arizona's Rashad Johnson while covering a punt. Carlson was in lateral pursuit of punt returner Patrick Peterson early in the fourth quarter when Johnson launched himself head first into Carlson's helmet to throw a block.
Frazier said the Vikings may send in tape of the hit for the NFL to review. Johnson may be in line for a fine of $21,000 if the NFL deems he had "impermissible use of the helmet."
Either way, Carlson almost certainly is going to be ruled out for Thursday's game against the Tampa Bay Buccaneers, just four days after he incurred the injury.
"We'll have to take him through the protocol over the next few days and in a short week. We don't expect him to probably (play Thursday)," Frazier said.
Carlson suffered a concussion in January 2011 during a Divisional Round playoff game when his Seattle Seahawks were playing against the Chicago Bears. In that game, Carlson hit the ground with his head, was knocked unconscious and was held overnight at a Chicago hospital for observation while his teammates returned to Seattle.
The fact that Carlson has suffered a serious concussion previously could have the Vikings proceeding cautiously in an era of heightened NFL awareness about concussions.
"That heightens the awareness of the doctors and medical people," Frazier said. "That gets their interest for sure."
If Carlson did indeed suffer a concussion Sunday, it would be the fourth of his career, dating back to his playing days at Notre Dame, according to ESPN.com.
Carlson missed the entire preseason with a sprained medial collateral ligament. He also missed the 2011 season with a torn labrum, and worked through oblique and hip injuries in 2010.
Carlson signed a five-year, $25 million free-agent contract with the Vikings in March that included a $5 million signing bonus. In six games, he has been targeted only six times, catching three passes for 8 yards.
As a rookie in 2008, he caught 55 passes for 627 yards and five touchdowns. The following season, he started all 16 games and caught 51 passes for 574 yards and seven touchdowns. The numbers dropped in 2010, when he had 31 receptions for 318 yards and one touchdown, and last year he spent the season on injured reserve.
Second-year player Kyle Rudolph has easily been used the most of the Vikings' tight ends. He has played in 94 percent of the 468 offensive snaps. Carlson has never played in more than 38 percent of the snaps, and overall has played in only 28 percent of the snaps. Rookie tight end Rhett Ellison has played in 19 percent of the offensive snaps this season.
Frazier said the Vikings would look at promoting tight end Allen Reisner from the practice squad this week, but that didn't happen in Monday's NFL transactions.
Tim Yotter is the publisher of Viking Update. Follow Viking Update on Twitter and discuss this topic on our message boards. To become a subscriber to the Viking Update web site or magazine, click here.
Vikings: ‘Heightened awareness' with Carlson
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