• Tracing the history of Eagles' head coaches and their commitment to winning at the line of scrimmage. It's a common denominator for success in the NFL.

How did the Eagles win the Super Bowl in February?

There were many factors, of course, and many intangibles that included incredible chemistry and confidence from the front office to the head coach to the roster. The Eagles overcame significant odds to win it all, and they enter 2018 as a very good, confident football team with one goal in mind. To try to boil it all down, the Eagles will have a chance to win every week as long as they take care of business at the line of scrimmage.

In the world of highlights and big plays and the glitz and glamour under the lights, the game of football comes down to the essentials: the offensive and defensive lines. And with Training Camp on the immediate horizon, the Eagles are well equipped on both sides of the line of scrimmage to contend.

When you step back and recognize the years that have gone by, with different head coaches and a variety of approaches to the game, the success at the line of scrimmage played right into the wins and losses on the scoreboard.

Buddy Ryan, way back in the 1980s and into the early 1990s, had himself one of the game's very best defensive lines with Reggie White and Clyde Simmons and Jerome Brown leading the way. The offensive line? Not so much. The names changed far too often. David Alexander was a fine center. Ron Heller was a scrappy tackle. Mike Schad was a tough guy at left guard. But the big offensive line move of the Ryan era was trading for a banged up and past-his-prime Ron Solt, and the Eagles struggled to score points in the playoffs and Ryan was eventually dismissed.

Rich Kotite tried to get it right by trading up to take Antone Davis in the first round of the 1991 draft, and then by using the draft to bring guard Lester Holmes (team's first pick, second round, 1993) and tackle Bernard Williams (first round) on board in 1994, but all three bombed out and didn't help the Eagles win in the trenches.

Then it was Ray Rhodes' turn, and yeah, Rhodes used the team's first pick in the 1995 pick on Mike Mamula, who had a much better career than he's been credited with, but still did not elevate to the level the Eagles needed, and later took defensive end Jon Harris in the first round of the 1997 draft. At least Rhodes had the right idea – in all four of the drafts when he was head coach, the Eagles used their first pick on linemen. Rhodes hit in 1996 on guard Jermane Mayberry and in 1998 on tackle Tra Thomas.

Andy Reid, as you remember, made it a priority to build the lines of scrimmage. He signed offensive tackle Jon Runyan in free agency. He used first-round draft picks on defensive tackle Corey Simon (hit), defensive end Jerome McDougle (miss), offensive tackle Shawn Andrews (hit, for the most part, just not long enough), defensive tackle Mike Patterson (hit), defensive tackle Brodrick Bunkley (meh), defensive end Brandon Graham (hit), guard Danny Watkins (miss), and, last but not least, defensive tackle Fletcher Cox (hit). He also traded for offensive tackle Jason Peters, hit big in the 2011 draft with center Jason Kelce, and continually reinforced the defensive in free agency (Jevon Kearse, for example).

In the three seasons of Chip Kelly, the offensive line was addressed only once in the draft, when Kelly nailed it in the first round of 2013, selecting offensive tackle Lane Johnson. Kelly's pick of defensive end Marcus Smith was a miss, but at least Kelly recognized the importance of the need. For the most part, though, Kelly did not address the offensive line, and that forced Howie Roseman to lead the charge to revamp the offensive line. The addition of Brandon Brooks in the 2016 free agency period was huge, as was the under-the-radar addition of Stefen Wisniewski in that same offseason.

Roseman also picked offensive linemen Isaac Seumalo and Halapoulivaati Vaitai in the 2016 draft and both have helped the Eagles weather injuries up front, Vaitai in particular. The defensive line has also been a priority, as the Eagles used the first draft pick in 2017 to take end Derek Barnett, added tackle Tim Jernigan and end Michael Bennett in trades, and signed Chris Long in free agency.

The Eagles are well stocked at the lines of scrimmage, and that, more than perhaps any other reason (OK, the quarterback situation is pretty good), is why the Eagles are positioned to make another deep run in 2018. The offensive line is as good as any in football, with some promising depth in Seumalo, Vaitai, and Chance Warmack at the head of the reserve class. The defensive line, while it enters Training Camp with questions due to injuries to Graham (ankle), Jernigan (back), and defensive tackle Haloti Ngata (elbow last year with Detroit) and some age on the edges, should be, when the regular season begins, completely ferocious.

We've seen it through the years. It's a time-tested formula that plays out in the NFL: When you win up front, you win in the standings. And the Eagles have made the commitment to win at the line of scrimmage, showing us over and over the value of dominating the line of scrimmage.