Anticipating practice squad promotion

FORT LAUDERDALE, Fla. -- One constant in Bill Belichick's tenure as Patriots coach is that the team usually enters a game with seven offensive linemen.

As part of that philosophy, Belichick has one backup who covers the center/guard spots in the event of injury and one backup who covers both tackle spots. The backups usually are utilized on the field-goal protection unit as well.

With this in mind, the Patriots are likely to promote an offensive lineman from the practice squad before tonight's season-opener. Otherwise, they'd be left with just six offensive linemen after declaring starting right tackle Sebastian Vollmer (back) and reserve center/guard Ryan Wendell (calf) out for the game. Considering that one of those linemen is veteran Brian Waters, who joined the team last Sunday, it further highlights the need for more depth.

Here is a bit more on each practice squad offensive lineman:

Nick McDonald -- A 6-foot-4, 305-pound center/guard from Grand Valley State who made the Packers' roster as a rookie free agent last year. He was with the Packers in training camp this year but didn't make the final cut. He was a game-day inactive for all of the Packers' 2010 games as the club viewed him as a developmental prospect (old Packers bio here). Quick hit: Viewed as the most likely to be promoted.

Matt Kopa -- The 6-foot-6, 303-pound tackle from Stanford entered the NFL as a rookie free agent with the 49ers last year. Kopa opened last season on the 49ers' practice squad before the Dolphins signed him to their 53-man roster on Nov. 9. Kopa didn't play in a game for the Dolphins in 2010, and was with them in training camp this year before being released at the 2011 final cutdown (old Stanford bio here). Quick hit: His time with the Dolphins could add value in a pinch.

Thomas Welch -- A 6-foot-7, 310-pound offensive tackle from Vanderbilt, he originally joined the Patriots as a seventh-round draft choice in 2010, with the team trading up to select him. Welch was released at the final 2010 roster cutdown and joined the Vikings' practice squad. The Vikings promoted him to their 53-man roster in December last year, but Welch didn't appear in a game. He was released at the final roster cutdown this year (old Vanderbilt bio). Quick hit: Having been with the Patriots in 2010 training camp gives him an edge from a learning-curve standpoint.