Football has changed a lot since Super Bowl I

Super Bowl I was played 49 years ago today, with the Green Bay Packersdefeating the Kansas City Chiefs 35-10 behind Bart Starr’s MVP performance and unlikely hero Max McGee.

Although the box score for the game might resemble one from 2015, the way the game was played, from rules to personnel to style, has changed quite a bit.

The field: The field in Super Bowl I was 120 yards long (including end zones) and 53 yards wide, but the location of a few landmarks were different:

- Goalposts for Super Bowl I were at the front of the end zone and not the rear. They weren’t moved to the rear of the end zone until the 1974 season (Super Bowl IX was played that season). None of the three passes thrown into the end zone in Super Bowl I hit the goalposts, though.

- The field’s hashmarks were much closer to the sideline and resembled those on a standard college football field. The hashmarks were moved to their current location in 1972.

This made passing outside much more difficult, since quarterbacks either had a narrower window to the outside or had to throw all the way back across the field. Super Bowl I quarterbacks combined to complete 26 percent (5-of-19) of their passes outside the field numbers, compared with 58.2 percent in the NFL this season.

The rules

Rules change constantly in the NFL, but a few changes gave a different look and feel to the game.

- Remember Deflate-gate and the controversy over the PSI of the balls? Well, in Super Bowl I, each team played with a different-sized ball. While on offense the Chiefs used AFL footballs, which were slightly longer and narrower (they were also thought to be easier to throw). The Packers used the standard NFL football.

- Kickoffs in Super Bowl I were from the kicking team’s 40-yard line. Kickoffs were moved to the 35 in 1974, to the 30 in 1994 and then back to the 35 in 2011.

Despite teams kicking from the 40-yard line, there were no touchbacks on the nine kickoffs in Super Bowl I, and only two of the kicks even reached the end zone. In 2015, 56 percent of kickoffs resulted in a touchback.

- Chiefs kicker Mike Mercer missed a 40-yard field goal in the first quarter, but instead of taking over at the line of scrimmage after the kick (the 33 ... remember, goalposts at the front of the end zone), the Packers got the ball at the 20. Teams didn't take over at the line of scrimmage after a missed kick (when the kick was beyond the 20) until 1974.

After the Packers went three-and-out, this led to a shorter field for the Chiefs, which helped them get their only touchdown of the game.

The play

Quarterbacks backpedaling on dropbacks and wide receivers lining up in three-point stances were the norm in Super Bowl I. It’s rare to see either today, but a few other norms in the style of play have become less common.

- There were no shotgun snaps in Super Bowl I (or II or III). There was one shotgun snap in Super Bowl IV, but it didn't return again until Super Bowl X. Nearly 62 percent of NFL plays in 2015 featured shotgun or pistol sets. Every team utilized shotgun or pistol sets at least 10 times in every game this season.

- In Super Bowl I, 89 percent of the plays from scrimmage featured a two-back backfield. Only 18 percent of plays in 2015 featured a two-back backfield, and there were only four instances of a team using those formations at least half of the time in a game.

- Quarterbacks dropped back to pass on 59 percent of plays in Super Bowl I (62 percent in 2015). However, the average pass in Super Bowl I traveled 14.3 yards past the line of scrimmage, about six yards farther than the average pass today (8.2).

- When teams ran the ball in Super Bowl I, there was more of an emphasis on getting outside: 47 percent of designed rushes in the game went outside the tackles (27 percent in 2015). The Packers rushed 20 times outside the tackles in Super Bowl I, twice as many times as the 2015 Packers had in any game. No team had 20 rushes outside the tackles in a game this season.