The man who was expected to start at center this year, Thomas Altieri, has suffered a concussion and is out indefinitely.

Thomas Altieri departed Arizona State’s morning practice on Monday with what coach Dennis Erickson said was a concussion, an ailment that will sideline the junior for an indefinite time.

Considering that he is trying to hold off redshirt freshman Garth Gerhart for the starting center job, Altieri potentially has a lot to lose by missing practice snaps.

"That position is still a flip of a coin," Erickson said. "I wouldn’t want to be out of there very long. That’s something that is evaluated every single day, If somebody is moved ahead of you, you have to go back and earn it. That is the nature of football."

Altieri, who has played in three games in two seasons, had a slight edge over Gerhart after spring practice. Last week, the 6-foot-2, 300-pounder said he felt he had become a more consistent blocker.

Concussions are difficult injuries to measure in terms of recovery time and prognosis. In contact sports, these types of injuries can be season-ending, depending on severity. Lets look at some notable concussions of the recent past.

On February 17, 2007, Brendan Shanahan of the New York Rangers suffered a concussion, which brought about serious symptoms of vertigo.

The room would spin when he did something as simple as bend over. He longed for a way to measure his healing, to know when he would be able to skate with his teammates again, but concussions offer no such benchmarks.

It wasn't until over a month later, on March 21, 2007, that Shanahan was able to take the ice again.

Patrice Bergeron of the Boston Bruins was lost for the season on October 27, 2007 when he was hit from behind into the boards. Missing 72 games, Bergeron has made a full recovery and will be ready for the 2008-2009 season.

However, a concussion of that severity can change a player's tactics on the ice or in the heat of the moment. Who knows if Bergeron will be half the player he was before the injury.

On the other hand, Ben Roethlisberger of the Pittsburgh Steelers suffered a concussion in Week 7 of the 2006 season against the Atlanta Falcons.

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A week later, Roethlisberger was back on the field, going 25/37 with one touchdown and four interceptions against the lowly Oakland Raiders. A week after that, he threw 3 interceptions against the Denver Broncos.

Was this a result of his concussion, or poor play? I believe they were linked. According the Mayo Clinic, there are many cognitive symptoms that go hand-in-hand with concussions.

The two most common concussion symptoms are confusion and amnesia. The amnesia, which may or may not be preceded by a loss of consciousness, almost always involves the loss of memory of the impact that caused the concussion.

Other immediate signs and symptoms of a concussion may include:

• Headache
• Dizziness
• Ringing in the ears
• Nausea or vomiting
• Slurred speech

Some symptoms of concussions don't appear until hours or days later. They include:

• Mood and cognitive disturbances
• Sensitivity to light and noise
• Sleep disturbances

These types of injuries can truly affect one's intensity and ability to perform on the gridiron. Hopefully, Altieri can make a quick and smooth recovery, with no lingering side effects like the ones Shanahan felt.

In the meantime, Garth Gerhart will be seeing the majority of the work with the first line. He was a teammate of our new right tackle, Adam Tello, at Norco High in California.